/* | |
* Licensed to the Apache Software Foundation (ASF) under one or more | |
* contributor license agreements. See the NOTICE file distributed with | |
* this work for additional information regarding copyright ownership. | |
* The ASF licenses this file to You under the Apache License, Version 2.0 | |
* (the "License"); you may not use this file except in compliance with | |
* the License. You may obtain a copy of the License at | |
* | |
* http://www.apache.org/licenses/LICENSE-2.0 | |
* | |
* Unless required by applicable law or agreed to in writing, software | |
* distributed under the License is distributed on an "AS IS" BASIS, | |
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
* See the License for the specific language governing permissions and | |
* limitations under the License. | |
*/ | |
package org.apache.commons.text; | |
import java.util.ArrayList; | |
import java.util.Enumeration; | |
import java.util.HashMap; | |
import java.util.List; | |
import java.util.Map; | |
import java.util.Properties; | |
import org.apache.commons.lang3.Validate; | |
import org.apache.commons.text.lookup.StringLookup; | |
import org.apache.commons.text.lookup.StringLookupFactory; | |
import org.apache.commons.text.matcher.StringMatcher; | |
import org.apache.commons.text.matcher.StringMatcherFactory; | |
/** | |
* Substitutes variables within a string by values. | |
* <p> | |
* This class takes a piece of text and substitutes all the variables within it. The default definition of a variable is | |
* {@code ${variableName}}. The prefix and suffix can be changed via constructors and set methods. | |
* </p> | |
* <p> | |
* Variable values are typically resolved from a map, but could also be resolved from system properties, or by supplying | |
* a custom variable resolver. | |
* <p> | |
* The simplest example is to use this class to replace Java System properties. For example: | |
* </p> | |
* | |
* <pre> | |
* StringSubstitutor | |
* .replaceSystemProperties("You are running with java.version = ${java.version} and os.name = ${os.name}."); | |
* </pre> | |
* | |
* <h2>Using a Custom Map</h2> | |
* <p> | |
* Typical usage of this class follows the following pattern: First an instance is created and initialized with the map | |
* that contains the values for the available variables. If a prefix and/or suffix for variables should be used other | |
* than the default ones, the appropriate settings can be performed. After that the {@code replace()} method can be | |
* called passing in the source text for interpolation. In the returned text all variable references (as long as their | |
* values are known) will be resolved. The following example demonstrates this: | |
* </p> | |
* | |
* <pre> | |
* Map<String, String> valuesMap = new HashMap<>(); | |
* valuesMap.put("animal", "quick brown fox"); | |
* valuesMap.put("target", "lazy dog"); | |
* String templateString = "The ${animal} jumped over the ${target}."; | |
* StringSubstitutor sub = new StringSubstitutor(valuesMap); | |
* String resolvedString = sub.replace(templateString); | |
* </pre> | |
* | |
* <p> | |
* yielding: | |
* </p> | |
* | |
* <pre> | |
* The quick brown fox jumped over the lazy dog. | |
* </pre> | |
* | |
* <h2>Providing Default Values</h2> | |
* <p> | |
* This class lets you set a default value for unresolved variables. The default value for a variable can be appended to | |
* the variable name after the variable default value delimiter. The default value of the variable default value | |
* delimiter is ':-', as in bash and other *nix shells, as those are arguably where the default ${} delimiter set | |
* originated. The variable default value delimiter can be manually set by calling | |
* {@link #setValueDelimiterMatcher(StringMatcher)}, {@link #setValueDelimiter(char)} or | |
* {@link #setValueDelimiter(String)}. The following shows an example with variable default value settings: | |
* </p> | |
* | |
* <pre> | |
* Map<String, String> valuesMap = new HashMap<>(); | |
* valuesMap.put("animal", "quick brown fox"); | |
* valuesMap.put("target", "lazy dog"); | |
* String templateString = "The ${animal} jumped over the ${target}. ${undefined.number:-1234567890}."; | |
* StringSubstitutor sub = new StringSubstitutor(valuesMap); | |
* String resolvedString = sub.replace(templateString); | |
* </pre> | |
* | |
* <p> | |
* yielding: | |
* </p> | |
* | |
* <pre> | |
* The quick brown fox jumped over the lazy dog. 1234567890. | |
* </pre> | |
* | |
* <p> | |
* {@code StringSubstitutor} supports throwing exceptions for unresolved variables, you enable this by setting calling | |
* {@link #setEnableUndefinedVariableException(boolean)} with {@code true}. | |
* </p> | |
* | |
* <h2>Reusing Instances</h2> | |
* <p> | |
* In addition to this usage pattern there are some static convenience methods that cover the most common use cases. | |
* These methods can be used without the need of manually creating an instance. However if multiple replace operations | |
* are to be performed, creating and reusing an instance of this class will be more efficient. | |
* </p> | |
* <p> | |
* This class is <b>not</b> thread safe. | |
* </p> | |
* | |
* <h2>Using Interpolation</h2> | |
* <p> | |
* The default interpolator let's you use string lookups like: | |
* </p> | |
* | |
* <pre> | |
final StringSubstitutor interpolator = StringSubstitutor.createInterpolator(); | |
interpolator.setEnableSubstitutionInVariables(true); // Allows for nested $'s. | |
final String text = interpolator.replace( | |
"Base64 Decoder: ${base64Decoder:SGVsbG9Xb3JsZCE=}\n" + | |
"Base64 Encoder: ${base64Encoder:HelloWorld!}\n" + | |
"Java Constant: ${const:java.awt.event.KeyEvent.VK_ESCAPE}\n" + | |
"Date: ${date:yyyy-MM-dd}\n" + | |
"DNS: ${dns:address|apache.org}\n" + | |
"Environment Variable: ${env:USERNAME}\n" + | |
"File Content: ${file:UTF-8:src/test/resources/document.properties}\n" + | |
"Java: ${java:version}\n" + | |
"Localhost: ${localhost:canonical-name}\n" + | |
"Properties File: ${properties:src/test/resources/document.properties::mykey}\n" + | |
"Resource Bundle: ${resourceBundle:org.example.testResourceBundleLookup:mykey}\n" + | |
"Script: ${script:javascript:3 + 4}\n" + | |
"System Property: ${sys:user.dir}\n" + | |
"URL Decoder: ${urlDecoder:Hello%20World%21}\n" + | |
"URL Encoder: ${urlEncoder:Hello World!}\n" + | |
"URL Content (HTTP): ${url:UTF-8:http://www.apache.org}\n" + | |
"URL Content (HTTPS): ${url:UTF-8:https://www.apache.org}\n" + | |
"URL Content (File): ${url:UTF-8:file:///${sys:user.dir}/src/test/resources/document.properties}\n" + | |
"XML XPath: ${xml:src/test/resources/document.xml:/root/path/to/node}\n" | |
); | |
* </pre> | |
* <p> | |
* For documentation of each lookup, see {@link StringLookupFactory}. | |
* </p> | |
* | |
* <h2>Using Recursive Variable Replacement</h2> | |
* <p> | |
* Variable replacement works in a recursive way. Thus, if a variable value contains a variable then that variable will | |
* also be replaced. Cyclic replacements are detected and will cause an exception to be thrown. | |
* </p> | |
* <p> | |
* Sometimes the interpolation's result must contain a variable prefix. As an example take the following source text: | |
* </p> | |
* | |
* <pre> | |
* The variable ${${name}} must be used. | |
* </pre> | |
* | |
* <p> | |
* Here only the variable's name referred to in the text should be replaced resulting in the text (assuming that the | |
* value of the {@code name} variable is {@code x}): | |
* </p> | |
* | |
* <pre> | |
* The variable ${x} must be used. | |
* </pre> | |
* | |
* <p> | |
* To achieve this effect there are two possibilities: Either set a different prefix and suffix for variables which do | |
* not conflict with the result text you want to produce. The other possibility is to use the escape character, by | |
* default '$'. If this character is placed before a variable reference, this reference is ignored and won't be | |
* replaced. For example: | |
* </p> | |
* | |
* <pre> | |
* The variable $${${name}} must be used. | |
* </pre> | |
* <p> | |
* In some complex scenarios you might even want to perform substitution in the names of variables, for instance | |
* </p> | |
* | |
* <pre> | |
* ${jre-${java.specification.version}} | |
* </pre> | |
* | |
* <p> | |
* {@code StringSubstitutor} supports this recursive substitution in variable names, but it has to be enabled explicitly | |
* by calling {@link #setEnableSubstitutionInVariables(boolean)} with {@code true}. | |
* </p> | |
* | |
* @since 1.3 | |
*/ | |
public class StringSubstitutor { | |
/** | |
* The default variable default separator. | |
* | |
* @since 1.5. | |
*/ | |
public static final String DEFAULT_VAR_DEFAULT = ":-"; | |
/** | |
* The default variable end separator. | |
* | |
* @since 1.5. | |
*/ | |
public static final String DEFAULT_VAR_END = "}"; | |
/** | |
* The default variable start separator. | |
* | |
* @since 1.5. | |
*/ | |
public static final String DEFAULT_VAR_START = "${"; | |
/** | |
* Constant for the default escape character. | |
*/ | |
public static final char DEFAULT_ESCAPE = '$'; | |
/** | |
* Constant for the default variable prefix. | |
*/ | |
public static final StringMatcher DEFAULT_PREFIX = StringMatcherFactory.INSTANCE.stringMatcher(DEFAULT_VAR_START); | |
/** | |
* Constant for the default variable suffix. | |
*/ | |
public static final StringMatcher DEFAULT_SUFFIX = StringMatcherFactory.INSTANCE.stringMatcher(DEFAULT_VAR_END); | |
/** | |
* Constant for the default value delimiter of a variable. | |
*/ | |
public static final StringMatcher DEFAULT_VALUE_DELIMITER = StringMatcherFactory.INSTANCE | |
.stringMatcher(DEFAULT_VAR_DEFAULT); | |
/** | |
* Creates a new instance using the interpolator string lookup | |
* {@link StringLookupFactory#interpolatorStringLookup()}. | |
* <p> | |
* This StringSubstitutor lets you perform substituions like: | |
* </p> | |
* | |
* <pre> | |
* StringSubstitutor.createInterpolator() | |
* .replace("OS name: ${sys:os.name}, " + "3 + 4 = ${script:javascript:3 + 4}"); | |
* </pre> | |
* | |
* @return a new instance using the interpolator string lookup. | |
* @see StringLookupFactory#interpolatorStringLookup() | |
* @since 1.8 | |
*/ | |
public static StringSubstitutor createInterpolator() { | |
return new StringSubstitutor(StringLookupFactory.INSTANCE.interpolatorStringLookup()); | |
} | |
/** | |
* Replaces all the occurrences of variables in the given source object with their matching values from the map. | |
* | |
* @param <V> the type of the values in the map | |
* @param source the source text containing the variables to substitute, null returns null | |
* @param valueMap the map with the values, may be null | |
* @return The result of the replace operation | |
* @throws IllegalArgumentException if a variable is not found and enableUndefinedVariableException is true | |
*/ | |
public static <V> String replace(final Object source, final Map<String, V> valueMap) { | |
return new StringSubstitutor(valueMap).replace(source); | |
} | |
/** | |
* Replaces all the occurrences of variables in the given source object with their matching values from the map. | |
* This method allows to specify a custom variable prefix and suffix | |
* | |
* @param <V> the type of the values in the map | |
* @param source the source text containing the variables to substitute, null returns null | |
* @param valueMap the map with the values, may be null | |
* @param prefix the prefix of variables, not null | |
* @param suffix the suffix of variables, not null | |
* @return The result of the replace operation | |
* @throws IllegalArgumentException if the prefix or suffix is null | |
* @throws IllegalArgumentException if a variable is not found and enableUndefinedVariableException is true | |
*/ | |
public static <V> String replace(final Object source, final Map<String, V> valueMap, final String prefix, | |
final String suffix) { | |
return new StringSubstitutor(valueMap, prefix, suffix).replace(source); | |
} | |
/** | |
* Replaces all the occurrences of variables in the given source object with their matching values from the | |
* properties. | |
* | |
* @param source the source text containing the variables to substitute, null returns null | |
* @param valueProperties the properties with values, may be null | |
* @return The result of the replace operation | |
* @throws IllegalArgumentException if a variable is not found and enableUndefinedVariableException is true | |
*/ | |
public static String replace(final Object source, final Properties valueProperties) { | |
if (valueProperties == null) { | |
return source.toString(); | |
} | |
final Map<String, String> valueMap = new HashMap<>(); | |
final Enumeration<?> propNames = valueProperties.propertyNames(); | |
while (propNames.hasMoreElements()) { | |
final String propName = (String) propNames.nextElement(); | |
final String propValue = valueProperties.getProperty(propName); | |
valueMap.put(propName, propValue); | |
} | |
return StringSubstitutor.replace(source, valueMap); | |
} | |
/** | |
* Replaces all the occurrences of variables in the given source object with their matching values from the system | |
* properties. | |
* | |
* @param source the source text containing the variables to substitute, null returns null | |
* @return The result of the replace operation | |
* @throws IllegalArgumentException if a variable is not found and enableUndefinedVariableException is true | |
*/ | |
public static String replaceSystemProperties(final Object source) { | |
return new StringSubstitutor(StringLookupFactory.INSTANCE.systemPropertyStringLookup()).replace(source); | |
} | |
/** | |
* Stores the escape character. | |
*/ | |
private char escapeChar; | |
/** | |
* Stores the variable prefix. | |
*/ | |
private StringMatcher prefixMatcher; | |
/** | |
* Stores the variable suffix. | |
*/ | |
private StringMatcher suffixMatcher; | |
/** | |
* Stores the default variable value delimiter. | |
*/ | |
private StringMatcher valueDelimiterMatcher; | |
/** | |
* Variable resolution is delegated to an implementor of {@link StringLookup}. | |
*/ | |
private StringLookup variableResolver; | |
/** | |
* The flag whether substitution in variable names is enabled. | |
*/ | |
private boolean enableSubstitutionInVariables; | |
/** | |
* Whether escapes should be preserved. Default is false; | |
*/ | |
private boolean preserveEscapes; | |
/** | |
* The flag whether substitution in variable values is disabled. | |
*/ | |
private boolean disableSubstitutionInValues; | |
/** | |
* The flag whether exception should be thrown on undefined variable. | |
*/ | |
private boolean enableUndefinedVariableException; | |
// ----------------------------------------------------------------------- | |
/** | |
* Creates a new instance with defaults for variable prefix and suffix and the escaping character. | |
*/ | |
public StringSubstitutor() { | |
this((StringLookup) null, DEFAULT_PREFIX, DEFAULT_SUFFIX, DEFAULT_ESCAPE); | |
} | |
/** | |
* Creates a new instance and initializes it. Uses defaults for variable prefix and suffix and the escaping | |
* character. | |
* | |
* @param <V> the type of the values in the map | |
* @param valueMap the map with the variables' values, may be null | |
*/ | |
public <V> StringSubstitutor(final Map<String, V> valueMap) { | |
this(StringLookupFactory.INSTANCE.mapStringLookup(valueMap), DEFAULT_PREFIX, DEFAULT_SUFFIX, DEFAULT_ESCAPE); | |
} | |
/** | |
* Creates a new instance and initializes it. Uses a default escaping character. | |
* | |
* @param <V> the type of the values in the map | |
* @param valueMap the map with the variables' values, may be null | |
* @param prefix the prefix for variables, not null | |
* @param suffix the suffix for variables, not null | |
* @throws IllegalArgumentException if the prefix or suffix is null | |
*/ | |
public <V> StringSubstitutor(final Map<String, V> valueMap, final String prefix, final String suffix) { | |
this(StringLookupFactory.INSTANCE.mapStringLookup(valueMap), prefix, suffix, DEFAULT_ESCAPE); | |
} | |
/** | |
* Creates a new instance and initializes it. | |
* | |
* @param <V> the type of the values in the map | |
* @param valueMap the map with the variables' values, may be null | |
* @param prefix the prefix for variables, not null | |
* @param suffix the suffix for variables, not null | |
* @param escape the escape character | |
* @throws IllegalArgumentException if the prefix or suffix is null | |
*/ | |
public <V> StringSubstitutor(final Map<String, V> valueMap, final String prefix, final String suffix, | |
final char escape) { | |
this(StringLookupFactory.INSTANCE.mapStringLookup(valueMap), prefix, suffix, escape); | |
} | |
/** | |
* Creates a new instance and initializes it. | |
* | |
* @param <V> the type of the values in the map | |
* @param valueMap the map with the variables' values, may be null | |
* @param prefix the prefix for variables, not null | |
* @param suffix the suffix for variables, not null | |
* @param escape the escape character | |
* @param valueDelimiter the variable default value delimiter, may be null | |
* @throws IllegalArgumentException if the prefix or suffix is null | |
*/ | |
public <V> StringSubstitutor(final Map<String, V> valueMap, final String prefix, final String suffix, | |
final char escape, final String valueDelimiter) { | |
this(StringLookupFactory.INSTANCE.mapStringLookup(valueMap), prefix, suffix, escape, valueDelimiter); | |
} | |
/** | |
* Creates a new instance and initializes it. | |
* | |
* @param variableResolver the variable resolver, may be null | |
*/ | |
public StringSubstitutor(final StringLookup variableResolver) { | |
this(variableResolver, DEFAULT_PREFIX, DEFAULT_SUFFIX, DEFAULT_ESCAPE); | |
} | |
/** | |
* Creates a new instance and initializes it. | |
* | |
* @param variableResolver the variable resolver, may be null | |
* @param prefix the prefix for variables, not null | |
* @param suffix the suffix for variables, not null | |
* @param escape the escape character | |
* @throws IllegalArgumentException if the prefix or suffix is null | |
*/ | |
public StringSubstitutor(final StringLookup variableResolver, final String prefix, final String suffix, | |
final char escape) { | |
this.setVariableResolver(variableResolver); | |
this.setVariablePrefix(prefix); | |
this.setVariableSuffix(suffix); | |
this.setEscapeChar(escape); | |
this.setValueDelimiterMatcher(DEFAULT_VALUE_DELIMITER); | |
} | |
/** | |
* Creates a new instance and initializes it. | |
* | |
* @param variableResolver the variable resolver, may be null | |
* @param prefix the prefix for variables, not null | |
* @param suffix the suffix for variables, not null | |
* @param escape the escape character | |
* @param valueDelimiter the variable default value delimiter string, may be null | |
* @throws IllegalArgumentException if the prefix or suffix is null | |
*/ | |
public StringSubstitutor(final StringLookup variableResolver, final String prefix, final String suffix, | |
final char escape, final String valueDelimiter) { | |
this.setVariableResolver(variableResolver); | |
this.setVariablePrefix(prefix); | |
this.setVariableSuffix(suffix); | |
this.setEscapeChar(escape); | |
this.setValueDelimiter(valueDelimiter); | |
} | |
/** | |
* Creates a new instance and initializes it. | |
* | |
* @param variableResolver the variable resolver, may be null | |
* @param prefixMatcher the prefix for variables, not null | |
* @param suffixMatcher the suffix for variables, not null | |
* @param escape the escape character | |
* @throws IllegalArgumentException if the prefix or suffix is null | |
*/ | |
public StringSubstitutor(final StringLookup variableResolver, final StringMatcher prefixMatcher, | |
final StringMatcher suffixMatcher, final char escape) { | |
this(variableResolver, prefixMatcher, suffixMatcher, escape, DEFAULT_VALUE_DELIMITER); | |
} | |
/** | |
* Creates a new instance and initializes it. | |
* | |
* @param variableResolver the variable resolver, may be null | |
* @param prefixMatcher the prefix for variables, not null | |
* @param suffixMatcher the suffix for variables, not null | |
* @param escape the escape character | |
* @param valueDelimiterMatcher the variable default value delimiter matcher, may be null | |
* @throws IllegalArgumentException if the prefix or suffix is null | |
*/ | |
public StringSubstitutor(final StringLookup variableResolver, final StringMatcher prefixMatcher, | |
final StringMatcher suffixMatcher, final char escape, final StringMatcher valueDelimiterMatcher) { | |
this.setVariableResolver(variableResolver); | |
this.setVariablePrefixMatcher(prefixMatcher); | |
this.setVariableSuffixMatcher(suffixMatcher); | |
this.setEscapeChar(escape); | |
this.setValueDelimiterMatcher(valueDelimiterMatcher); | |
} | |
/** | |
* Checks if the specified variable is already in the stack (list) of variables. | |
* | |
* @param varName the variable name to check | |
* @param priorVariables the list of prior variables | |
*/ | |
private void checkCyclicSubstitution(final String varName, final List<String> priorVariables) { | |
if (!priorVariables.contains(varName)) { | |
return; | |
} | |
final TextStringBuilder buf = new TextStringBuilder(256); | |
buf.append("Infinite loop in property interpolation of "); | |
buf.append(priorVariables.remove(0)); | |
buf.append(": "); | |
buf.appendWithSeparators(priorVariables, "->"); | |
throw new IllegalStateException(buf.toString()); | |
} | |
// Escape | |
// ----------------------------------------------------------------------- | |
/** | |
* Returns the escape character. | |
* | |
* @return The character used for escaping variable references | |
*/ | |
public char getEscapeChar() { | |
return this.escapeChar; | |
} | |
// Resolver | |
// ----------------------------------------------------------------------- | |
/** | |
* Gets the StringLookup that is used to lookup variables. | |
* | |
* @return The StringLookup | |
*/ | |
public StringLookup getStringLookup() { | |
return this.variableResolver; | |
} | |
// Variable Default Value Delimiter | |
// ----------------------------------------------------------------------- | |
/** | |
* Gets the variable default value delimiter matcher currently in use. | |
* <p> | |
* The variable default value delimiter is the character or characters that delimite the variable name and the | |
* variable default value. This delimiter is expressed in terms of a matcher allowing advanced variable default | |
* value delimiter matches. | |
* <p> | |
* If it returns null, then the variable default value resolution is disabled. | |
* | |
* @return The variable default value delimiter matcher in use, may be null | |
*/ | |
public StringMatcher getValueDelimiterMatcher() { | |
return valueDelimiterMatcher; | |
} | |
// Prefix | |
// ----------------------------------------------------------------------- | |
/** | |
* Gets the variable prefix matcher currently in use. | |
* <p> | |
* The variable prefix is the character or characters that identify the start of a variable. This prefix is | |
* expressed in terms of a matcher allowing advanced prefix matches. | |
* | |
* @return The prefix matcher in use | |
*/ | |
public StringMatcher getVariablePrefixMatcher() { | |
return prefixMatcher; | |
} | |
// Suffix | |
// ----------------------------------------------------------------------- | |
/** | |
* Gets the variable suffix matcher currently in use. | |
* <p> | |
* The variable suffix is the character or characters that identify the end of a variable. This suffix is expressed | |
* in terms of a matcher allowing advanced suffix matches. | |
* | |
* @return The suffix matcher in use | |
*/ | |
public StringMatcher getVariableSuffixMatcher() { | |
return suffixMatcher; | |
} | |
/** | |
* Returns a flag whether substitution is disabled in variable values.If set to <b>true</b>, the values of variables | |
* can contain other variables will not be processed and substituted original variable is evaluated, e.g. | |
* | |
* <pre> | |
* Map<String, String> valuesMap = new HashMap<>(); | |
* valuesMap.put("name", "Douglas ${surname}"); | |
* valuesMap.put("surname", "Crockford"); | |
* String templateString = "Hi ${name}"; | |
* StrSubstitutor sub = new StrSubstitutor(valuesMap); | |
* String resolvedString = sub.replace(templateString); | |
* </pre> | |
* | |
* yielding: | |
* | |
* <pre> | |
* Hi Douglas ${surname} | |
* </pre> | |
* | |
* @return The substitution in variable values flag | |
*/ | |
public boolean isDisableSubstitutionInValues() { | |
return disableSubstitutionInValues; | |
} | |
// Substitution support in variable names | |
// ----------------------------------------------------------------------- | |
/** | |
* Returns a flag whether substitution is done in variable names. | |
* | |
* @return The substitution in variable names flag | |
*/ | |
public boolean isEnableSubstitutionInVariables() { | |
return enableSubstitutionInVariables; | |
} | |
/** | |
* Returns a flag whether exception can be thrown upon undefined variable. | |
* | |
* @return The fail on undefined variable flag | |
*/ | |
public boolean isEnableUndefinedVariableException() { | |
return enableUndefinedVariableException; | |
} | |
/** | |
* Returns the flag controlling whether escapes are preserved during substitution. | |
* | |
* @return The preserve escape flag | |
*/ | |
public boolean isPreserveEscapes() { | |
return preserveEscapes; | |
} | |
// ----------------------------------------------------------------------- | |
/** | |
* Replaces all the occurrences of variables with their matching values from the resolver using the given source | |
* array as a template. The array is not altered by this method. | |
* | |
* @param source the character array to replace in, not altered, null returns null | |
* @return The result of the replace operation | |
* @throws IllegalArgumentException if variable is not found when its allowed to throw exception | |
*/ | |
public String replace(final char[] source) { | |
if (source == null) { | |
return null; | |
} | |
final TextStringBuilder buf = new TextStringBuilder(source.length).append(source); | |
substitute(buf, 0, source.length); | |
return buf.toString(); | |
} | |
/** | |
* Replaces all the occurrences of variables with their matching values from the resolver using the given source | |
* array as a template. The array is not altered by this method. | |
* <p> | |
* Only the specified portion of the array will be processed. The rest of the array is not processed, and is not | |
* returned. | |
* | |
* @param source the character array to replace in, not altered, null returns null | |
* @param offset the start offset within the array, must be valid | |
* @param length the length within the array to be processed, must be valid | |
* @return The result of the replace operation | |
* @throws IllegalArgumentException if variable is not found when its allowed to throw exception | |
*/ | |
public String replace(final char[] source, final int offset, final int length) { | |
if (source == null) { | |
return null; | |
} | |
final TextStringBuilder buf = new TextStringBuilder(length).append(source, offset, length); | |
substitute(buf, 0, length); | |
return buf.toString(); | |
} | |
/** | |
* Replaces all the occurrences of variables with their matching values from the resolver using the given source as | |
* a template. The source is not altered by this method. | |
* | |
* @param source the buffer to use as a template, not changed, null returns null | |
* @return The result of the replace operation | |
* @throws IllegalArgumentException if variable is not found when its allowed to throw exception | |
*/ | |
public String replace(final CharSequence source) { | |
if (source == null) { | |
return null; | |
} | |
return replace(source, 0, source.length()); | |
} | |
/** | |
* Replaces all the occurrences of variables with their matching values from the resolver using the given source as | |
* a template. The source is not altered by this method. | |
* <p> | |
* Only the specified portion of the buffer will be processed. The rest of the buffer is not processed, and is not | |
* returned. | |
* | |
* @param source the buffer to use as a template, not changed, null returns null | |
* @param offset the start offset within the array, must be valid | |
* @param length the length within the array to be processed, must be valid | |
* @return The result of the replace operation | |
* @throws IllegalArgumentException if variable is not found when its allowed to throw exception | |
*/ | |
public String replace(final CharSequence source, final int offset, final int length) { | |
if (source == null) { | |
return null; | |
} | |
final TextStringBuilder buf = new TextStringBuilder(length).append(source.toString(), offset, length); | |
substitute(buf, 0, length); | |
return buf.toString(); | |
} | |
// ----------------------------------------------------------------------- | |
/** | |
* Replaces all the occurrences of variables in the given source object with their matching values from the | |
* resolver. The input source object is converted to a string using {@code toString} and is not altered. | |
* | |
* @param source the source to replace in, null returns null | |
* @return The result of the replace operation | |
* @throws IllegalArgumentException if a variable is not found and enableUndefinedVariableException is true | |
*/ | |
public String replace(final Object source) { | |
if (source == null) { | |
return null; | |
} | |
final TextStringBuilder buf = new TextStringBuilder().append(source); | |
substitute(buf, 0, buf.length()); | |
return buf.toString(); | |
} | |
// ----------------------------------------------------------------------- | |
/** | |
* Replaces all the occurrences of variables with their matching values from the resolver using the given source | |
* string as a template. | |
* | |
* @param source the string to replace in, null returns null | |
* @return The result of the replace operation | |
* @throws IllegalArgumentException if variable is not found when its allowed to throw exception | |
*/ | |
public String replace(final String source) { | |
if (source == null) { | |
return null; | |
} | |
final TextStringBuilder buf = new TextStringBuilder(source); | |
if (!substitute(buf, 0, source.length())) { | |
return source; | |
} | |
return buf.toString(); | |
} | |
/** | |
* Replaces all the occurrences of variables with their matching values from the resolver using the given source | |
* string as a template. | |
* <p> | |
* Only the specified portion of the string will be processed. The rest of the string is not processed, and is not | |
* returned. | |
* | |
* @param source the string to replace in, null returns null | |
* @param offset the start offset within the array, must be valid | |
* @param length the length within the array to be processed, must be valid | |
* @return The result of the replace operation | |
* @throws IllegalArgumentException if variable is not found when its allowed to throw exception | |
*/ | |
public String replace(final String source, final int offset, final int length) { | |
if (source == null) { | |
return null; | |
} | |
final TextStringBuilder buf = new TextStringBuilder(length).append(source, offset, length); | |
if (!substitute(buf, 0, length)) { | |
return source.substring(offset, offset + length); | |
} | |
return buf.toString(); | |
} | |
// ----------------------------------------------------------------------- | |
/** | |
* Replaces all the occurrences of variables with their matching values from the resolver using the given source | |
* buffer as a template. The buffer is not altered by this method. | |
* | |
* @param source the buffer to use as a template, not changed, null returns null | |
* @return The result of the replace operation | |
* @throws IllegalArgumentException if variable is not found when its allowed to throw exception | |
*/ | |
public String replace(final StringBuffer source) { | |
if (source == null) { | |
return null; | |
} | |
final TextStringBuilder buf = new TextStringBuilder(source.length()).append(source); | |
substitute(buf, 0, buf.length()); | |
return buf.toString(); | |
} | |
/** | |
* Replaces all the occurrences of variables with their matching values from the resolver using the given source | |
* buffer as a template. The buffer is not altered by this method. | |
* <p> | |
* Only the specified portion of the buffer will be processed. The rest of the buffer is not processed, and is not | |
* returned. | |
* | |
* @param source the buffer to use as a template, not changed, null returns null | |
* @param offset the start offset within the array, must be valid | |
* @param length the length within the array to be processed, must be valid | |
* @return The result of the replace operation | |
* @throws IllegalArgumentException if variable is not found when its allowed to throw exception | |
*/ | |
public String replace(final StringBuffer source, final int offset, final int length) { | |
if (source == null) { | |
return null; | |
} | |
final TextStringBuilder buf = new TextStringBuilder(length).append(source, offset, length); | |
substitute(buf, 0, length); | |
return buf.toString(); | |
} | |
// ----------------------------------------------------------------------- | |
/** | |
* Replaces all the occurrences of variables with their matching values from the resolver using the given source | |
* builder as a template. The builder is not altered by this method. | |
* | |
* @param source the builder to use as a template, not changed, null returns null | |
* @return The result of the replace operation | |
* @throws IllegalArgumentException if variable is not found when its allowed to throw exception | |
*/ | |
public String replace(final TextStringBuilder source) { | |
if (source == null) { | |
return null; | |
} | |
final TextStringBuilder buf = new TextStringBuilder(source.length()).append(source); | |
substitute(buf, 0, buf.length()); | |
return buf.toString(); | |
} | |
/** | |
* Replaces all the occurrences of variables with their matching values from the resolver using the given source | |
* builder as a template. The builder is not altered by this method. | |
* <p> | |
* Only the specified portion of the builder will be processed. The rest of the builder is not processed, and is not | |
* returned. | |
* | |
* @param source the builder to use as a template, not changed, null returns null | |
* @param offset the start offset within the array, must be valid | |
* @param length the length within the array to be processed, must be valid | |
* @return The result of the replace operation | |
* @throws IllegalArgumentException if variable is not found when its allowed to throw exception | |
*/ | |
public String replace(final TextStringBuilder source, final int offset, final int length) { | |
if (source == null) { | |
return null; | |
} | |
final TextStringBuilder buf = new TextStringBuilder(length).append(source, offset, length); | |
substitute(buf, 0, length); | |
return buf.toString(); | |
} | |
// ----------------------------------------------------------------------- | |
/** | |
* Replaces all the occurrences of variables within the given source buffer with their matching values from the | |
* resolver. The buffer is updated with the result. | |
* | |
* @param source the buffer to replace in, updated, null returns zero | |
* @return true if altered | |
*/ | |
public boolean replaceIn(final StringBuffer source) { | |
if (source == null) { | |
return false; | |
} | |
return replaceIn(source, 0, source.length()); | |
} | |
/** | |
* Replaces all the occurrences of variables within the given source buffer with their matching values from the | |
* resolver. The buffer is updated with the result. | |
* <p> | |
* Only the specified portion of the buffer will be processed. The rest of the buffer is not processed, but it is | |
* not deleted. | |
* | |
* @param source the buffer to replace in, updated, null returns zero | |
* @param offset the start offset within the array, must be valid | |
* @param length the length within the buffer to be processed, must be valid | |
* @return true if altered | |
* @throws IllegalArgumentException if variable is not found when its allowed to throw exception | |
*/ | |
public boolean replaceIn(final StringBuffer source, final int offset, final int length) { | |
if (source == null) { | |
return false; | |
} | |
final TextStringBuilder buf = new TextStringBuilder(length).append(source, offset, length); | |
if (!substitute(buf, 0, length)) { | |
return false; | |
} | |
source.replace(offset, offset + length, buf.toString()); | |
return true; | |
} | |
// ----------------------------------------------------------------------- | |
/** | |
* Replaces all the occurrences of variables within the given source buffer with their matching values from the | |
* resolver. The buffer is updated with the result. | |
* | |
* @param source the buffer to replace in, updated, null returns zero | |
* @return true if altered | |
*/ | |
public boolean replaceIn(final StringBuilder source) { | |
if (source == null) { | |
return false; | |
} | |
return replaceIn(source, 0, source.length()); | |
} | |
/** | |
* Replaces all the occurrences of variables within the given source builder with their matching values from the | |
* resolver. The builder is updated with the result. | |
* <p> | |
* Only the specified portion of the buffer will be processed. The rest of the buffer is not processed, but it is | |
* not deleted. | |
* | |
* @param source the buffer to replace in, updated, null returns zero | |
* @param offset the start offset within the array, must be valid | |
* @param length the length within the buffer to be processed, must be valid | |
* @return true if altered | |
* @throws IllegalArgumentException if variable is not found when its allowed to throw exception | |
*/ | |
public boolean replaceIn(final StringBuilder source, final int offset, final int length) { | |
if (source == null) { | |
return false; | |
} | |
final TextStringBuilder buf = new TextStringBuilder(length).append(source, offset, length); | |
if (!substitute(buf, 0, length)) { | |
return false; | |
} | |
source.replace(offset, offset + length, buf.toString()); | |
return true; | |
} | |
// ----------------------------------------------------------------------- | |
/** | |
* Replaces all the occurrences of variables within the given source builder with their matching values from the | |
* resolver. | |
* | |
* @param source the builder to replace in, updated, null returns zero | |
* @return true if altered | |
* @throws IllegalArgumentException if variable is not found when its allowed to throw exception | |
*/ | |
public boolean replaceIn(final TextStringBuilder source) { | |
if (source == null) { | |
return false; | |
} | |
return substitute(source, 0, source.length()); | |
} | |
/** | |
* Replaces all the occurrences of variables within the given source builder with their matching values from the | |
* resolver. | |
* <p> | |
* Only the specified portion of the builder will be processed. The rest of the builder is not processed, but it is | |
* not deleted. | |
* | |
* @param source the builder to replace in, null returns zero | |
* @param offset the start offset within the array, must be valid | |
* @param length the length within the builder to be processed, must be valid | |
* @return true if altered | |
* @throws IllegalArgumentException if variable is not found when its allowed to throw exception | |
*/ | |
public boolean replaceIn(final TextStringBuilder source, final int offset, final int length) { | |
if (source == null) { | |
return false; | |
} | |
return substitute(source, offset, length); | |
} | |
/** | |
* Internal method that resolves the value of a variable. | |
* <p> | |
* Most users of this class do not need to call this method. This method is called automatically by the substitution | |
* process. | |
* <p> | |
* Writers of subclasses can override this method if they need to alter how each substitution occurs. The method is | |
* passed the variable's name and must return the corresponding value. This implementation uses the | |
* {@link #getStringLookup()} with the variable's name as the key. | |
* | |
* @param variableName the name of the variable, not null | |
* @param buf the buffer where the substitution is occurring, not null | |
* @param startPos the start position of the variable including the prefix, valid | |
* @param endPos the end position of the variable including the suffix, valid | |
* @return The variable's value or <b>null</b> if the variable is unknown | |
*/ | |
protected String resolveVariable(final String variableName, final TextStringBuilder buf, final int startPos, | |
final int endPos) { | |
final StringLookup resolver = getStringLookup(); | |
if (resolver == null) { | |
return null; | |
} | |
return resolver.lookup(variableName); | |
} | |
/** | |
* Sets a flag whether substitution is done in variable values (recursive). | |
* | |
* @param disableSubstitutionInValues true if substitution in variable value are disabled | |
* @return this, to enable chaining | |
*/ | |
public StringSubstitutor setDisableSubstitutionInValues(final boolean disableSubstitutionInValues) { | |
this.disableSubstitutionInValues = disableSubstitutionInValues; | |
return this; | |
} | |
/** | |
* Sets a flag whether substitution is done in variable names. If set to <b>true</b>, the names of variables can | |
* contain other variables which are processed first before the original variable is evaluated, e.g. | |
* {@code ${jre-${java.version}}}. The default value is <b>false</b>. | |
* | |
* @param enableSubstitutionInVariables the new value of the flag | |
* @return this, to enable chaining | |
*/ | |
public StringSubstitutor setEnableSubstitutionInVariables(final boolean enableSubstitutionInVariables) { | |
this.enableSubstitutionInVariables = enableSubstitutionInVariables; | |
return this; | |
} | |
/** | |
* Sets a flag whether exception should be thrown if any variable is undefined. | |
* | |
* @param failOnUndefinedVariable true if exception should be thrown on undefined variable | |
* @return this, to enable chaining | |
*/ | |
public StringSubstitutor setEnableUndefinedVariableException(final boolean failOnUndefinedVariable) { | |
this.enableUndefinedVariableException = failOnUndefinedVariable; | |
return this; | |
} | |
/** | |
* Sets the escape character. If this character is placed before a variable reference in the source text, this | |
* variable will be ignored. | |
* | |
* @param escapeCharacter the escape character (0 for disabling escaping) | |
* @return this, to enable chaining | |
*/ | |
public StringSubstitutor setEscapeChar(final char escapeCharacter) { | |
this.escapeChar = escapeCharacter; | |
return this; | |
} | |
/** | |
* Sets a flag controlling whether escapes are preserved during substitution. If set to <b>true</b>, the escape | |
* character is retained during substitution (e.g. {@code $${this-is-escaped}} remains | |
* {@code $${this-is-escaped}}). If set to <b>false</b>, the escape character is removed during substitution | |
* (e.g. {@code $${this-is-escaped}} becomes {@code ${this-is-escaped}}). The default value is | |
* <b>false</b> | |
* | |
* @param preserveEscapes true if escapes are to be preserved | |
* @return this, to enable chaining | |
*/ | |
public StringSubstitutor setPreserveEscapes(final boolean preserveEscapes) { | |
this.preserveEscapes = preserveEscapes; | |
return this; | |
} | |
/** | |
* Sets the variable default value delimiter to use. | |
* <p> | |
* The variable default value delimiter is the character or characters that delimite the variable name and the | |
* variable default value. This method allows a single character variable default value delimiter to be easily set. | |
* | |
* @param valueDelimiter the variable default value delimiter character to use | |
* @return this, to enable chaining | |
*/ | |
public StringSubstitutor setValueDelimiter(final char valueDelimiter) { | |
return setValueDelimiterMatcher(StringMatcherFactory.INSTANCE.charMatcher(valueDelimiter)); | |
} | |
/** | |
* Sets the variable default value delimiter to use. | |
* <p> | |
* The variable default value delimiter is the character or characters that delimite the variable name and the | |
* variable default value. This method allows a string variable default value delimiter to be easily set. | |
* <p> | |
* If the {@code valueDelimiter} is null or empty string, then the variable default value resolution becomes | |
* disabled. | |
* | |
* @param valueDelimiter the variable default value delimiter string to use, may be null or empty | |
* @return this, to enable chaining | |
*/ | |
public StringSubstitutor setValueDelimiter(final String valueDelimiter) { | |
if (valueDelimiter == null || valueDelimiter.length() == 0) { | |
setValueDelimiterMatcher(null); | |
return this; | |
} | |
return setValueDelimiterMatcher(StringMatcherFactory.INSTANCE.stringMatcher(valueDelimiter)); | |
} | |
/** | |
* Sets the variable default value delimiter matcher to use. | |
* <p> | |
* The variable default value delimiter is the character or characters that delimite the variable name and the | |
* variable default value. This delimiter is expressed in terms of a matcher allowing advanced variable default | |
* value delimiter matches. | |
* <p> | |
* If the {@code valueDelimiterMatcher} is null, then the variable default value resolution becomes disabled. | |
* | |
* @param valueDelimiterMatcher variable default value delimiter matcher to use, may be null | |
* @return this, to enable chaining | |
*/ | |
public StringSubstitutor setValueDelimiterMatcher(final StringMatcher valueDelimiterMatcher) { | |
this.valueDelimiterMatcher = valueDelimiterMatcher; | |
return this; | |
} | |
/** | |
* Sets the variable prefix to use. | |
* <p> | |
* The variable prefix is the character or characters that identify the start of a variable. This method allows a | |
* single character prefix to be easily set. | |
* | |
* @param prefix the prefix character to use | |
* @return this, to enable chaining | |
*/ | |
public StringSubstitutor setVariablePrefix(final char prefix) { | |
return setVariablePrefixMatcher(StringMatcherFactory.INSTANCE.charMatcher(prefix)); | |
} | |
/** | |
* Sets the variable prefix to use. | |
* <p> | |
* The variable prefix is the character or characters that identify the start of a variable. This method allows a | |
* string prefix to be easily set. | |
* | |
* @param prefix the prefix for variables, not null | |
* @return this, to enable chaining | |
* @throws IllegalArgumentException if the prefix is null | |
*/ | |
public StringSubstitutor setVariablePrefix(final String prefix) { | |
Validate.isTrue(prefix != null, "Variable prefix must not be null!"); | |
return setVariablePrefixMatcher(StringMatcherFactory.INSTANCE.stringMatcher(prefix)); | |
} | |
/** | |
* Sets the variable prefix matcher currently in use. | |
* <p> | |
* The variable prefix is the character or characters that identify the start of a variable. This prefix is | |
* expressed in terms of a matcher allowing advanced prefix matches. | |
* | |
* @param prefixMatcher the prefix matcher to use, null ignored | |
* @return this, to enable chaining | |
* @throws IllegalArgumentException if the prefix matcher is null | |
*/ | |
public StringSubstitutor setVariablePrefixMatcher(final StringMatcher prefixMatcher) { | |
Validate.isTrue(prefixMatcher != null, "Variable prefix matcher must not be null!"); | |
this.prefixMatcher = prefixMatcher; | |
return this; | |
} | |
/** | |
* Sets the VariableResolver that is used to lookup variables. | |
* | |
* @param variableResolver the VariableResolver | |
* @return this, to enable chaining | |
*/ | |
public StringSubstitutor setVariableResolver(final StringLookup variableResolver) { | |
this.variableResolver = variableResolver; | |
return this; | |
} | |
/** | |
* Sets the variable suffix to use. | |
* <p> | |
* The variable suffix is the character or characters that identify the end of a variable. This method allows a | |
* single character suffix to be easily set. | |
* | |
* @param suffix the suffix character to use | |
* @return this, to enable chaining | |
*/ | |
public StringSubstitutor setVariableSuffix(final char suffix) { | |
return setVariableSuffixMatcher(StringMatcherFactory.INSTANCE.charMatcher(suffix)); | |
} | |
/** | |
* Sets the variable suffix to use. | |
* <p> | |
* The variable suffix is the character or characters that identify the end of a variable. This method allows a | |
* string suffix to be easily set. | |
* | |
* @param suffix the suffix for variables, not null | |
* @return this, to enable chaining | |
* @throws IllegalArgumentException if the suffix is null | |
*/ | |
public StringSubstitutor setVariableSuffix(final String suffix) { | |
Validate.isTrue(suffix != null, "Variable suffix must not be null!"); | |
return setVariableSuffixMatcher(StringMatcherFactory.INSTANCE.stringMatcher(suffix)); | |
} | |
/** | |
* Sets the variable suffix matcher currently in use. | |
* <p> | |
* The variable suffix is the character or characters that identify the end of a variable. This suffix is expressed | |
* in terms of a matcher allowing advanced suffix matches. | |
* | |
* @param suffixMatcher the suffix matcher to use, null ignored | |
* @return this, to enable chaining | |
* @throws IllegalArgumentException if the suffix matcher is null | |
*/ | |
public StringSubstitutor setVariableSuffixMatcher(final StringMatcher suffixMatcher) { | |
Validate.isTrue(suffixMatcher != null, "Variable suffix matcher must not be null!"); | |
this.suffixMatcher = suffixMatcher; | |
return this; | |
} | |
// ----------------------------------------------------------------------- | |
/** | |
* Internal method that substitutes the variables. | |
* <p> | |
* Most users of this class do not need to call this method. This method will be called automatically by another | |
* (public) method. | |
* <p> | |
* Writers of subclasses can override this method if they need access to the substitution process at the start or | |
* end. | |
* | |
* @param buf the string builder to substitute into, not null | |
* @param offset the start offset within the builder, must be valid | |
* @param length the length within the builder to be processed, must be valid | |
* @return true if altered | |
*/ | |
protected boolean substitute(final TextStringBuilder buf, final int offset, final int length) { | |
return substitute(buf, offset, length, null) > 0; | |
} | |
/** | |
* Recursive handler for multiple levels of interpolation. This is the main interpolation method, which resolves the | |
* values of all variable references contained in the passed in text. | |
* | |
* @param buf the string builder to substitute into, not null | |
* @param offset the start offset within the builder, must be valid | |
* @param length the length within the builder to be processed, must be valid | |
* @param priorVariables the stack keeping track of the replaced variables, may be null | |
* @return The length change that occurs, unless priorVariables is null when the int represents a boolean flag as to | |
* whether any change occurred. | |
* @throws IllegalArgumentException if variable is not found when its allowed to throw exception | |
*/ | |
private int substitute(final TextStringBuilder buf, final int offset, final int length, | |
List<String> priorVariables) { | |
final StringMatcher pfxMatcher = getVariablePrefixMatcher(); | |
final StringMatcher suffMatcher = getVariableSuffixMatcher(); | |
final char escape = getEscapeChar(); | |
final StringMatcher valueDelimMatcher = getValueDelimiterMatcher(); | |
final boolean substitutionInVariablesEnabled = isEnableSubstitutionInVariables(); | |
final boolean substitutionInValuesDisabled = isDisableSubstitutionInValues(); | |
final boolean undefinedVariableException = isEnableUndefinedVariableException(); | |
final boolean top = priorVariables == null; | |
boolean altered = false; | |
int lengthChange = 0; | |
char[] chars = buf.buffer; | |
int bufEnd = offset + length; | |
int pos = offset; | |
while (pos < bufEnd) { | |
final int startMatchLen = pfxMatcher.isMatch(chars, pos, offset, bufEnd); | |
if (startMatchLen == 0) { | |
pos++; | |
} else { | |
// found variable start marker | |
if (pos > offset && chars[pos - 1] == escape) { | |
// escaped | |
if (preserveEscapes) { | |
pos++; | |
continue; | |
} | |
buf.deleteCharAt(pos - 1); | |
chars = buf.buffer; // in case buffer was altered | |
lengthChange--; | |
altered = true; | |
bufEnd--; | |
} else { | |
// find suffix | |
final int startPos = pos; | |
pos += startMatchLen; | |
int endMatchLen = 0; | |
int nestedVarCount = 0; | |
while (pos < bufEnd) { | |
if (substitutionInVariablesEnabled && pfxMatcher.isMatch(chars, pos, offset, bufEnd) != 0) { | |
// found a nested variable start | |
endMatchLen = pfxMatcher.isMatch(chars, pos, offset, bufEnd); | |
nestedVarCount++; | |
pos += endMatchLen; | |
continue; | |
} | |
endMatchLen = suffMatcher.isMatch(chars, pos, offset, bufEnd); | |
if (endMatchLen == 0) { | |
pos++; | |
} else { | |
// found variable end marker | |
if (nestedVarCount == 0) { | |
String varNameExpr = new String(chars, startPos + startMatchLen, | |
pos - startPos - startMatchLen); | |
if (substitutionInVariablesEnabled) { | |
final TextStringBuilder bufName = new TextStringBuilder(varNameExpr); | |
substitute(bufName, 0, bufName.length()); | |
varNameExpr = bufName.toString(); | |
} | |
pos += endMatchLen; | |
final int endPos = pos; | |
String varName = varNameExpr; | |
String varDefaultValue = null; | |
if (valueDelimMatcher != null) { | |
final char[] varNameExprChars = varNameExpr.toCharArray(); | |
int valueDelimiterMatchLen = 0; | |
for (int i = 0; i < varNameExprChars.length; i++) { | |
// if there's any nested variable when nested variable substitution disabled, | |
// then stop resolving name and default value. | |
if (!substitutionInVariablesEnabled && pfxMatcher.isMatch(varNameExprChars, i, | |
i, varNameExprChars.length) != 0) { | |
break; | |
} | |
if (valueDelimMatcher.isMatch(varNameExprChars, i, 0, | |
varNameExprChars.length) != 0) { | |
valueDelimiterMatchLen = valueDelimMatcher.isMatch(varNameExprChars, i, 0, | |
varNameExprChars.length); | |
varName = varNameExpr.substring(0, i); | |
varDefaultValue = varNameExpr.substring(i + valueDelimiterMatchLen); | |
break; | |
} | |
} | |
} | |
// on the first call initialize priorVariables | |
if (priorVariables == null) { | |
priorVariables = new ArrayList<>(); | |
priorVariables.add(new String(chars, offset, length)); | |
} | |
// handle cyclic substitution | |
checkCyclicSubstitution(varName, priorVariables); | |
priorVariables.add(varName); | |
// resolve the variable | |
String varValue = resolveVariable(varName, buf, startPos, endPos); | |
if (varValue == null) { | |
varValue = varDefaultValue; | |
} | |
if (varValue != null) { | |
final int varLen = varValue.length(); | |
buf.replace(startPos, endPos, varValue); | |
altered = true; | |
int change = 0; | |
if (!substitutionInValuesDisabled) { // recursive replace | |
change = substitute(buf, startPos, varLen, priorVariables); | |
} | |
change = change + varLen - (endPos - startPos); | |
pos += change; | |
bufEnd += change; | |
lengthChange += change; | |
chars = buf.buffer; // in case buffer was altered | |
} else if (undefinedVariableException) { | |
throw new IllegalArgumentException(String.format( | |
"Cannot resolve variable '%s' (enableSubstitutionInVariables=%s).", varName, | |
enableSubstitutionInVariables)); | |
} | |
// remove variable from the cyclic stack | |
priorVariables.remove(priorVariables.size() - 1); | |
break; | |
} | |
nestedVarCount--; | |
pos += endMatchLen; | |
} | |
} | |
} | |
} | |
} | |
if (top) { | |
return altered ? 1 : 0; | |
} | |
return lengthChange; | |
} | |
} |