| /* |
| * 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.configuration2; |
| |
| import java.math.BigDecimal; |
| import java.math.BigInteger; |
| import java.util.Collection; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.Properties; |
| |
| /** |
| * <p>The main interface for accessing configuration data in a read-only fashion.</p> |
| * <p> |
| * The major part of the methods defined in this interface deals with accessing |
| * properties of various data types. There is a generic {@code getProperty()} |
| * method, which returns the value of the queried property in its raw data |
| * type. Other getter methods try to convert this raw data type into a specific |
| * data type. If this fails, a {@code ConversionException} will be thrown.</p> |
| * <p>For most of the property getter methods an overloaded version exists that |
| * allows to specify a default value, which will be returned if the queried |
| * property cannot be found in the configuration. The behavior of the methods |
| * that do not take a default value in case of a missing property is not defined |
| * by this interface and depends on a concrete implementation. E.g. the |
| * {@link AbstractConfiguration} class, which is the base class |
| * of most configuration implementations provided by this package, per default |
| * returns <b>null</b> if a property is not found, but provides the |
| * {@link AbstractConfiguration#setThrowExceptionOnMissing(boolean) |
| * setThrowExceptionOnMissing()} |
| * method, with which it can be configured to throw a {@code NoSuchElementException} |
| * exception in that case. (Note that getter methods for primitive types in |
| * {@code AbstractConfiguration} always throw an exception for missing |
| * properties because there is no way of overloading the return value.)</p> |
| * |
| * @version $Id$ |
| * @since 2.0 |
| */ |
| public interface ImmutableConfiguration |
| { |
| /** |
| * Check if the configuration is empty. |
| * |
| * @return {@code true} if the configuration contains no property, |
| * {@code false} otherwise. |
| */ |
| boolean isEmpty(); |
| |
| /** |
| * Returns the number of keys stored in this configuration. Note that a |
| * concrete implementation is not guaranteed to be efficient; for some |
| * implementations it may be expensive to determine the size. Especially, if |
| * you just want to check whether a configuration is empty, it is preferable |
| * to use the {@link #isEmpty()} method. |
| * |
| * @return the number of keys stored in this configuration |
| */ |
| int size(); |
| |
| /** |
| * Check if the configuration contains the specified key. |
| * |
| * @param key the key whose presence in this configuration is to be tested |
| * |
| * @return {@code true} if the configuration contains a value for this |
| * key, {@code false} otherwise |
| */ |
| boolean containsKey(String key); |
| |
| /** |
| * Gets a property from the configuration. This is the most basic get |
| * method for retrieving values of properties. In a typical implementation |
| * of the {@code Configuration} interface the other get methods (that |
| * return specific data types) will internally make use of this method. On |
| * this level variable substitution is not yet performed. The returned |
| * object is an internal representation of the property value for the passed |
| * in key. It is owned by the {@code Configuration} object. So a caller |
| * should not modify this object. It cannot be guaranteed that this object |
| * will stay constant over time (i.e. further update operations on the |
| * configuration may change its internal state). |
| * |
| * @param key property to retrieve |
| * @return the value to which this configuration maps the specified key, or |
| * null if the configuration contains no mapping for this key. |
| */ |
| Object getProperty(String key); |
| |
| /** |
| * Get the list of the keys contained in the configuration that match the |
| * specified prefix. For instance, if the configuration contains the |
| * following keys:<br> |
| * {@code db.user, db.pwd, db.url, window.xpos, window.ypos},<br> |
| * an invocation of {@code getKeys("db");}<br> |
| * will return the keys below:<br> |
| * {@code db.user, db.pwd, db.url}.<br> |
| * Note that the prefix itself is included in the result set if there is a |
| * matching key. The exact behavior - how the prefix is actually |
| * interpreted - depends on a concrete implementation. |
| * |
| * @param prefix The prefix to test against. |
| * @return An Iterator of keys that match the prefix. |
| * @see #getKeys() |
| */ |
| Iterator<String> getKeys(String prefix); |
| |
| /** |
| * Get the list of the keys contained in the configuration. The returned |
| * iterator can be used to obtain all defined keys. It does not allow |
| * removing elements from this configuration via its {@code remove()} |
| * method. |
| * |
| * @return An Iterator. |
| */ |
| Iterator<String> getKeys(); |
| |
| /** |
| * Get a list of properties associated with the given configuration key. This method |
| * expects the given key to have an arbitrary number of String values, each of which |
| * is of the form {@code key=value}. These strings are split at the equals sign, and |
| * the key parts will become keys of the returned {@code Properties} object, the value |
| * parts become values. |
| * |
| * @param key The configuration key. |
| * @return The associated properties if key is found. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a String/List. |
| * @throws IllegalArgumentException if one of the tokens is malformed (does not contain |
| * an equals sign). |
| */ |
| Properties getProperties(String key); |
| |
| /** |
| * Get a boolean associated with the given configuration key. |
| * |
| * @param key The configuration key. |
| * @return The associated boolean. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a Boolean. |
| */ |
| boolean getBoolean(String key); |
| |
| /** |
| * Get a boolean associated with the given configuration key. If the key doesn't map |
| * to an existing object, the default value is returned. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * @return The associated boolean. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a Boolean. |
| */ |
| boolean getBoolean(String key, boolean defaultValue); |
| |
| /** |
| * Get a {@link Boolean} associated with the given configuration key. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * @return The associated boolean if key is found and has valid format, default value |
| * otherwise. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a Boolean. |
| */ |
| Boolean getBoolean(String key, Boolean defaultValue); |
| |
| /** |
| * Get a byte associated with the given configuration key. |
| * |
| * @param key The configuration key. |
| * @return The associated byte. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a Byte. |
| */ |
| byte getByte(String key); |
| |
| /** |
| * Get a byte associated with the given configuration key. If the key doesn't map to |
| * an existing object, the default value is returned. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * @return The associated byte. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a Byte. |
| */ |
| byte getByte(String key, byte defaultValue); |
| |
| /** |
| * Get a {@link Byte} associated with the given configuration key. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * @return The associated byte if key is found and has valid format, default value |
| * otherwise. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a Byte. |
| */ |
| Byte getByte(String key, Byte defaultValue); |
| |
| /** |
| * Get a double associated with the given configuration key. |
| * |
| * @param key The configuration key. |
| * @return The associated double. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a Double. |
| */ |
| double getDouble(String key); |
| |
| /** |
| * Get a double associated with the given configuration key. If the key doesn't map to |
| * an existing object, the default value is returned. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * @return The associated double. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a Double. |
| */ |
| double getDouble(String key, double defaultValue); |
| |
| /** |
| * Get a {@link Double} associated with the given configuration key. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * @return The associated double if key is found and has valid format, default value |
| * otherwise. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a Double. |
| */ |
| Double getDouble(String key, Double defaultValue); |
| |
| /** |
| * Get a float associated with the given configuration key. |
| * |
| * @param key The configuration key. |
| * @return The associated float. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a Float. |
| */ |
| float getFloat(String key); |
| |
| /** |
| * Get a float associated with the given configuration key. If the key doesn't map to |
| * an existing object, the default value is returned. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * @return The associated float. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a Float. |
| */ |
| float getFloat(String key, float defaultValue); |
| |
| /** |
| * Get a {@link Float} associated with the given configuration key. If the key doesn't |
| * map to an existing object, the default value is returned. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * @return The associated float if key is found and has valid format, default value |
| * otherwise. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a Float. |
| */ |
| Float getFloat(String key, Float defaultValue); |
| |
| /** |
| * Get a int associated with the given configuration key. |
| * |
| * @param key The configuration key. |
| * @return The associated int. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a Integer. |
| */ |
| int getInt(String key); |
| |
| /** |
| * Get a int associated with the given configuration key. If the key doesn't map to an |
| * existing object, the default value is returned. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * @return The associated int. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a Integer. |
| */ |
| int getInt(String key, int defaultValue); |
| |
| /** |
| * Get an {@link Integer} associated with the given configuration key. If the key |
| * doesn't map to an existing object, the default value is returned. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * @return The associated int if key is found and has valid format, default value |
| * otherwise. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a Integer. |
| */ |
| Integer getInteger(String key, Integer defaultValue); |
| |
| /** |
| * Get a long associated with the given configuration key. |
| * |
| * @param key The configuration key. |
| * @return The associated long. |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the |
| * key maps to an object that is not a Long. |
| */ |
| long getLong(String key); |
| |
| /** |
| * Get a long associated with the given configuration key. |
| * If the key doesn't map to an existing object, the default value |
| * is returned. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * @return The associated long. |
| * |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the key maps to an |
| * object that is not a Long. |
| */ |
| long getLong(String key, long defaultValue); |
| |
| /** |
| * Get a {@link Long} associated with the given configuration key. |
| * If the key doesn't map to an existing object, the default value |
| * is returned. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * @return The associated long if key is found and has valid |
| * format, default value otherwise. |
| * |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the key maps to an |
| * object that is not a Long. |
| */ |
| Long getLong(String key, Long defaultValue); |
| |
| /** |
| * Get a short associated with the given configuration key. |
| * |
| * @param key The configuration key. |
| * @return The associated short. |
| * |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the key maps to an |
| * object that is not a Short. |
| */ |
| short getShort(String key); |
| |
| /** |
| * Get a short associated with the given configuration key. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * @return The associated short. |
| * |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the key maps to an |
| * object that is not a Short. |
| */ |
| short getShort(String key, short defaultValue); |
| |
| /** |
| * Get a {@link Short} associated with the given configuration key. |
| * If the key doesn't map to an existing object, the default value |
| * is returned. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * @return The associated short if key is found and has valid |
| * format, default value otherwise. |
| * |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the key maps to an |
| * object that is not a Short. |
| */ |
| Short getShort(String key, Short defaultValue); |
| |
| /** |
| * Get a {@link BigDecimal} associated with the given configuration key. |
| * |
| * @param key The configuration key. |
| * @return The associated BigDecimal if key is found and has valid format |
| */ |
| BigDecimal getBigDecimal(String key); |
| |
| /** |
| * Get a {@link BigDecimal} associated with the given configuration key. |
| * If the key doesn't map to an existing object, the default value |
| * is returned. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * |
| * @return The associated BigDecimal if key is found and has valid |
| * format, default value otherwise. |
| */ |
| BigDecimal getBigDecimal(String key, BigDecimal defaultValue); |
| |
| /** |
| * Get a {@link BigInteger} associated with the given configuration key. |
| * |
| * @param key The configuration key. |
| * |
| * @return The associated BigInteger if key is found and has valid format |
| */ |
| BigInteger getBigInteger(String key); |
| |
| /** |
| * Get a {@link BigInteger} associated with the given configuration key. |
| * If the key doesn't map to an existing object, the default value |
| * is returned. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * |
| * @return The associated BigInteger if key is found and has valid |
| * format, default value otherwise. |
| */ |
| BigInteger getBigInteger(String key, BigInteger defaultValue); |
| |
| /** |
| * Get a string associated with the given configuration key. |
| * |
| * @param key The configuration key. |
| * @return The associated string. |
| * |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the key maps to an object that |
| * is not a String. |
| */ |
| String getString(String key); |
| |
| /** |
| * Get a string associated with the given configuration key. |
| * If the key doesn't map to an existing object, the default value |
| * is returned. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * @return The associated string if key is found and has valid |
| * format, default value otherwise. |
| * |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the key maps to an object that |
| * is not a String. |
| */ |
| String getString(String key, String defaultValue); |
| |
| /** |
| * Get the value of a string property that is stored in encoded form in this |
| * configuration. This method obtains the value of the string property |
| * identified by the given key. This value is then passed to the provided |
| * {@code ConfigurationDecoder}. The value returned by the |
| * {@code ConfigurationDecoder} is passed to the caller. If the key is not |
| * associated with a value, the decoder is not invoked; depending on this |
| * configuration's settings either <b>null</b> is returned or an exception |
| * is thrown. |
| * |
| * @param key the configuration key |
| * @param decoder the {@code ConfigurationDecoder} (must not be <b>null</b>) |
| * @return the plain string value of the specified encoded property |
| * @throws IllegalArgumentException if a <b>null</b> decoder is passed |
| */ |
| String getEncodedString(String key, ConfigurationDecoder decoder); |
| |
| /** |
| * Get the value of a string property that is stored in encoded form in this |
| * configuration using a default {@code ConfigurationDecoder}. This method |
| * works like the method with the same name, but it uses a default |
| * {@code ConfigurationDecoder} associated with this configuration. It |
| * depends on a specific implementation how this default decoder is |
| * obtained. |
| * |
| * @param key the configuration key |
| * @return the plain string value of the specified encoded property |
| */ |
| String getEncodedString(String key); |
| |
| /** |
| * Get an array of strings associated with the given configuration key. |
| * If the key doesn't map to an existing object an empty array is returned |
| * |
| * @param key The configuration key. |
| * @return The associated string array if key is found. |
| * |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the key maps to an |
| * object that is not a String/List of Strings. |
| */ |
| String[] getStringArray(String key); |
| |
| /** |
| * Get a List of the values associated with the given configuration key. |
| * This method is different from the generic {@code getList()} method in |
| * that it does not recursively obtain all values stored for the specified |
| * property key. Rather, only the first level of the hierarchy is processed. |
| * So the resulting list may contain complex objects like arrays or |
| * collections - depending on the storage structure used by a concrete |
| * subclass. If the key doesn't map to an existing object, an empty List is |
| * returned. |
| * |
| * @param key The configuration key. |
| * @return The associated List. |
| * |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the key maps to an |
| * object that is not a List. |
| */ |
| List<Object> getList(String key); |
| |
| /** |
| * Get a List of strings associated with the given configuration key. |
| * If the key doesn't map to an existing object, the default value |
| * is returned. |
| * |
| * @param key The configuration key. |
| * @param defaultValue The default value. |
| * @return The associated List of strings. |
| * |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the key maps to an |
| * object that is not a List. |
| * @see #getList(Class, String, List) |
| */ |
| List<Object> getList(String key, List<?> defaultValue); |
| |
| /** |
| * Get an object of the specified type associated with the given |
| * configuration key. If the key doesn't map to an existing object, the |
| * method returns null unless |
| * {@link AbstractConfiguration#isThrowExceptionOnMissing()} is set to |
| * {@code true}. |
| * |
| * @param <T> the target type of the value |
| * @param cls the target class of the value |
| * @param key the key of the value |
| * @return the value of the requested type for the key |
| * @throws java.util.NoSuchElementException if the key doesn't map to an existing |
| * object and {@code throwExceptionOnMissing=true} |
| * @throws org.apache.commons.configuration2.ex.ConversionException if the value is not compatible with the |
| * requested type |
| * @since 2.0 |
| */ |
| <T> T get(Class<T> cls, String key); |
| |
| /** |
| * Get an object of the specified type associated with the given |
| * configuration key using a default value. If the key doesn't map to an |
| * existing object, the default value is returned. |
| * |
| * @param <T> the target type of the value |
| * @param cls the target class of the value |
| * @param key the key of the value |
| * @param defaultValue the default value |
| * |
| * @return the value of the requested type for the key |
| * |
| * @throws org.apache.commons.configuration2.ex.ConversionException if the value is not |
| * compatible with the requested type |
| * |
| * @since 2.0 |
| */ |
| <T> T get(Class<T> cls, String key, T defaultValue); |
| |
| /** |
| * Get an array of typed objects associated with the given configuration key. |
| * If the key doesn't map to an existing object, an empty list is returned. |
| * |
| * @param cls the type expected for the elements of the array |
| * @param key The configuration key. |
| * @return The associated array if the key is found, and the value compatible with the type specified. |
| * |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the key maps to an object that |
| * is not compatible with a list of the specified class. |
| * |
| * @since 2.0 |
| */ |
| Object getArray(Class<?> cls, String key); |
| |
| /** |
| * Get an array of typed objects associated with the given configuration key. |
| * If the key doesn't map to an existing object, the default value is returned. |
| * |
| * @param cls the type expected for the elements of the array |
| * @param key the configuration key. |
| * @param defaultValue the default value |
| * @return The associated array if the key is found, and the value compatible with the type specified. |
| * |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the key maps to an object that |
| * is not compatible with an array of the specified class. |
| * @throws IllegalArgumentException if the default value is not an array of the specified type |
| * |
| * @since 2.0 |
| * @deprecated This method should not be used any more because its signature |
| * does not allow type-safe invocations; use {@link #get(Class, String, Object)} |
| * instead which offers the same functionality; for instance, to query for an |
| * array of ints use |
| * {@code int[] result = config.get(int[].class, "myArrayKey", someDefault);}. |
| */ |
| @Deprecated |
| Object getArray(Class<?> cls, String key, Object defaultValue); |
| |
| /** |
| * Get a list of typed objects associated with the given configuration key |
| * returning an empty list if the key doesn't map to an existing object. |
| * |
| * @param <T> the type expected for the elements of the list |
| * @param cls the class expected for the elements of the list |
| * @param key The configuration key. |
| * @return The associated list if the key is found. |
| * |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the key maps to an object that |
| * is not compatible with a list of the specified class. |
| * |
| * @since 2.0 |
| */ |
| <T> List<T> getList(Class<T> cls, String key); |
| |
| /** |
| * Get a list of typed objects associated with the given configuration key |
| * returning the specified default value if the key doesn't map to an |
| * existing object. This method recursively retrieves all values stored |
| * for the passed in key, i.e. if one of these values is again a complex |
| * object like an array or a collection (which may be the case for some |
| * concrete subclasses), all values are extracted and added to the |
| * resulting list - performing a type conversion if necessary. |
| * |
| * @param <T> the type expected for the elements of the list |
| * @param cls the class expected for the elements of the list |
| * @param key the configuration key. |
| * @param defaultValue the default value. |
| * @return The associated List. |
| * |
| * @throws org.apache.commons.configuration2.ex.ConversionException is thrown if the key maps to an object that |
| * is not compatible with a list of the specified class. |
| * |
| * @since 2.0 |
| */ |
| <T> List<T> getList(Class<T> cls, String key, List<T> defaultValue); |
| |
| /** |
| * Get a collection of typed objects associated with the given configuration |
| * key. This method works like |
| * {@link #getCollection(Class, String, Collection, Collection)} passing in |
| * <b>null</b> as default value. |
| * |
| * @param <T> the element type of the result list |
| * @param cls the the element class of the result list |
| * @param key the configuration key |
| * @param target the target collection (may be <b>null</b>) |
| * @return the collection to which data was added |
| * @throws org.apache.commons.configuration2.ex.ConversionException if the conversion is not possible |
| * @since 2.0 |
| */ |
| <T> Collection<T> getCollection(Class<T> cls, String key, |
| Collection<T> target); |
| |
| /** |
| * Get a collection of typed objects associated with the given configuration |
| * key using the values in the specified default collection if the key does |
| * not map to an existing object. This method is similar to |
| * {@code getList()}, however, it allows specifying a target collection. |
| * Results are added to this collection. This is useful if the data |
| * retrieved should be added to a specific kind of collection, e.g. a set to |
| * remove duplicates. The return value is as follows: |
| * <ul> |
| * <li>If the key does not map to an existing object and the default value |
| * is <b>null</b>, the method returns <b>null</b>.</li> |
| * <li>If the target collection is not <b>null</b> and data has been added |
| * (either from the resolved property value or from the default collection), |
| * the target collection is returned.</li> |
| * <li>If the target collection is <b>null</b> and data has been added |
| * (either from the resolved property value or from the default collection), |
| * return value is the target collection created by this method.</li> |
| * </ul> |
| * |
| * @param <T> the element type of the result list |
| * @param cls the the element class of the result list |
| * @param key the configuration key |
| * @param target the target collection (may be <b>null</b>) |
| * @param defaultValue the default value (may be <b>null</b>) |
| * @return the collection to which data was added |
| * @throws org.apache.commons.configuration2.ex.ConversionException if the conversion is not possible |
| * @since 2.0 |
| */ |
| <T> Collection<T> getCollection(Class<T> cls, String key, |
| Collection<T> target, Collection<T> defaultValue); |
| |
| /** |
| * Return a decorator immutable Configuration containing every key from the current |
| * Configuration that starts with the specified prefix. The prefix is |
| * removed from the keys in the subset. For example, if the configuration |
| * contains the following properties: |
| * |
| * <pre> |
| * prefix.number = 1 |
| * prefix.string = Apache |
| * prefixed.foo = bar |
| * prefix = Jakarta</pre> |
| * |
| * the immutable Configuration returned by {@code subset("prefix")} will contain |
| * the properties: |
| * |
| * <pre> |
| * number = 1 |
| * string = Apache |
| * = Jakarta</pre> |
| * |
| * (The key for the value "Jakarta" is an empty string) |
| * |
| * @param prefix The prefix used to select the properties. |
| * @return a subset immutable configuration |
| */ |
| ImmutableConfiguration immutableSubset(String prefix); |
| } |