src/main/java/org/apache/freemarker/onlinetester/util/DataModelParser.java - freemarker-online-tester - Git at Google

 /*
  * 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.freemarker.onlinetester.util;

 import java.io.IOException;
 import java.io.StringReader;
 import java.math.BigDecimal;
 import java.sql.Time;
 import java.sql.Timestamp;
 import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.TimeZone;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;

 import javax.xml.parsers.DocumentBuilder;

 import org.apache.commons.lang3.StringUtils;
 import org.w3c.dom.Document;
 import org.xml.sax.ErrorHandler;
 import org.xml.sax.InputSource;
 import org.xml.sax.SAXException;

 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;

 import freemarker.ext.dom.NodeModel;
 import freemarker.template.utility.DateUtil;
 import freemarker.template.utility.DateUtil.CalendarFieldsToDateConverter;
 import freemarker.template.utility.DateUtil.DateParseException;
 import freemarker.template.utility.DateUtil.TrivialCalendarFieldsToDateConverter;

 /**
  * Parses the text that the user enters into the data model input field.
  */
 public final class DataModelParser {

     private static final String KEYWORD_NEGATIVE_INFINITY = "-Infinity";

     private static final String KEYWORD_POSITIVE_INFINITY = "+Infinity";

     private static final String KEYWORD_INFINITY = "Infinity";

     private static final String KEYWORD_TRUE = "true";

     private static final String KEYWORD_FALSE = "false";

     private static final String KEYWORD_NULL = "null";

     private static final String KEYWORD_NAN = "NaN";

     /** Matches a line starting like "someVariable=". */
     private static final Pattern ASSIGNMENT_START = Pattern.compile(
             "^\\s*"
             + "(\\p{L}[\\p{L}\\p{N}\\.:\\-_$@]*)" // name
             + "[ \t]*=\\s*",
             Pattern.MULTILINE);

     /** Matches a value that starts like a number, or probably meant to be number at least. */
     private static final Pattern NUMBER_LIKE = Pattern.compile("[+-]?[\\.,]?[0-9].*", Pattern.DOTALL);

     private static final ObjectMapper JSON_MAPPER = new ObjectMapper();

     private DataModelParser() {
         // Not meant to be instantiated
     }

     public static Map<String, Object> parse(String src, TimeZone timeZone) throws DataModelParsingException {
         if (StringUtils.isBlank(src)) {
             return Collections.emptyMap();
         }

         Map<String, Object> dataModel = new LinkedHashMap<>();

         String lastName = null;
         int lastAssignmentStartEnd = 0;
         final Matcher assignmentStart = ASSIGNMENT_START.matcher(src);
         findAssignments: while (true) {
             boolean hasNextAssignment = assignmentStart.find(lastAssignmentStartEnd);

             if (lastName != null) {
                 String value = src.substring(
                         lastAssignmentStartEnd, hasNextAssignment ? assignmentStart.start() : src.length())
                         .trim();
                 final Object parsedValue;
                 try {
                     parsedValue = parseValue(value, timeZone);
                 } catch (DataModelParsingException e) {
                     throw new DataModelParsingException(
                             "Failed to parse the value of \"" + lastName + "\":\n" + e.getMessage(), e.getCause());
                 }
                 dataModel.put(lastName, parsedValue);
             }

             if (lastName == null && (!hasNextAssignment || assignmentStart.start() != 0)) {
                 throw new DataModelParsingException(
                         "The data model specification must start with an assignment (name=value).");
             }

             if (!hasNextAssignment) {
                 break findAssignments;
             }

             lastName = assignmentStart.group(1).trim();
             lastAssignmentStartEnd = assignmentStart.end();
         }

         return dataModel;
     }

     private static Object parseValue(String value, TimeZone timeZone) throws DataModelParsingException {
         // Note: Because we fall back to interpret the input as a literal string value when it doesn't look like
         // anything else (like a number, boolean, etc.), it's important to avoid misunderstandings, and throw exception
         // in suspicious situations. The user can always quote the string value if we are "too smart". But he will
         // be confused about the rules of FreeMarker if what he believes to be a non-string is misinterpreted by this
         // parser as a string. Getting sometimes an error and then quoting the string is better than that.

         if (value.endsWith(";")) {  // Tolerate this habit of Java and JavaScript programmers
             value = value.substring(value.length() - 1).trim();
         }

         if (NUMBER_LIKE.matcher(value).matches()) {
             try {
                 return new BigDecimal(value);
             } catch (NumberFormatException e) {
                 // Maybe it's a ISO 8601 Date/time/datetime
                 CalendarFieldsToDateConverter calToDateConverter = new TrivialCalendarFieldsToDateConverter();

                 DateParseException attemptedTemportalPExc = null;
                 String attemptedTemporalType = null;
                 final int dashIdx = value.indexOf('-');
                 final int colonIdx = value.indexOf(':');
                 if (value.indexOf('T') > 1 || (dashIdx > 1 && colonIdx > dashIdx)) {
                     try {
                         return new Timestamp(
                                 DateUtil.parseISO8601DateTime(value, timeZone, calToDateConverter).getTime());
                     } catch (DateParseException pExc) {
                         attemptedTemporalType = "date-time";
                         attemptedTemportalPExc = pExc;
                     }
                 } else if (dashIdx > 1) {
                     try {
                         return new java.sql.Date(
                                 DateUtil.parseISO8601Date(value, timeZone, calToDateConverter).getTime());
                     } catch (DateParseException pExc) {
                         attemptedTemporalType = "date";
                         attemptedTemportalPExc = pExc;
                     }
                 } else if (colonIdx > 1) {
                     try {
                         return new Time(
                                 DateUtil.parseISO8601Time(value, timeZone, calToDateConverter).getTime());
                     } catch (DateParseException pExc) {
                         attemptedTemporalType = "time";
                         attemptedTemportalPExc = pExc;
                     }
                 }
                 if (attemptedTemportalPExc == null) {
                     throw new DataModelParsingException("Malformed number: " + value, e);
                 } else {
                     throw new DataModelParsingException(
                             "Malformed ISO 8601 " + attemptedTemporalType + " (or malformed number): " +
                             attemptedTemportalPExc.getMessage(), e.getCause());
                 }
             }
         } else if (value.startsWith("\"")) {
             try {
                 return JSON_MAPPER.readValue(value, String.class);
             } catch (IOException e) {
                 throw new DataModelParsingException(
                         "Malformed quoted string (using JSON syntax): " + getMessageWithoutLocation(e),
                         e);
             }
         } else if (value.startsWith("\'")) {
             throw new DataModelParsingException(
                     "Malformed quoted string (using JSON syntax): Use \" character for quotation, not \' character.");
         } else if (value.startsWith("[")) {
             try {
                 return JSON_MAPPER.readValue(value, List.class);
             } catch (IOException e) {
                 throw new DataModelParsingException(
                         "Malformed list (using JSON syntax): " + getMessageWithoutLocation(e),
                         e);
             }
         } else if (value.startsWith("{")) {
             try {
                 return JSON_MAPPER.readValue(value, LinkedHashMap.class);
             } catch (IOException e) {
                 throw new DataModelParsingException(
                         "Malformed list (using JSON syntax): " + getMessageWithoutLocation(e),
                         e);
             }
         } else if (value.startsWith("<")) {
             try {
                 DocumentBuilder builder = NodeModel.getDocumentBuilderFactory().newDocumentBuilder();
                 ErrorHandler errorHandler = NodeModel.getErrorHandler();
                 if (errorHandler != null) builder.setErrorHandler(errorHandler);
                 final Document doc = builder.parse(new InputSource(new StringReader(value)));
                 NodeModel.simplify(doc);
                 return doc;
             } catch (SAXException e) {
                 final String saxMsg = e.getMessage();
                 throw new DataModelParsingException("Malformed XML: " + (saxMsg != null ? saxMsg : e), e);
             } catch (Exception e) {
                 throw new DataModelParsingException("XML parsing has failed with internal error: " + e, e);
             }
         } else if (value.equalsIgnoreCase(KEYWORD_TRUE)) {
             checkKeywordCase(value, KEYWORD_TRUE);
             return Boolean.TRUE;
         } else if (value.equalsIgnoreCase(KEYWORD_FALSE)) {
             checkKeywordCase(value, KEYWORD_FALSE);
             return Boolean.FALSE;
         } else if (value.equalsIgnoreCase(KEYWORD_NULL)) {
             checkKeywordCase(value, KEYWORD_NULL);
             return null;
         } else if (value.equalsIgnoreCase(KEYWORD_NAN)) {
             checkKeywordCase(value, KEYWORD_NAN);
             return Double.NaN;
         } else if (value.equalsIgnoreCase(KEYWORD_INFINITY)) {
             checkKeywordCase(value, KEYWORD_INFINITY);
             return Double.POSITIVE_INFINITY;
         } else if (value.equalsIgnoreCase(KEYWORD_POSITIVE_INFINITY)) {
             checkKeywordCase(value, KEYWORD_POSITIVE_INFINITY);
             return Double.POSITIVE_INFINITY;
         } else if (value.equalsIgnoreCase(KEYWORD_NEGATIVE_INFINITY)) {
             checkKeywordCase(value, KEYWORD_NEGATIVE_INFINITY);
             return Double.NEGATIVE_INFINITY;
         } else if (value.length() == 0) {
             throw new DataModelParsingException(
                     "Empty value. (If you indeed wanted a 0 length string, quote it, like \"\".)");
         } else {
             return value;
         }
     }

     private static String getMessageWithoutLocation(IOException e) {
         return e instanceof JsonProcessingException
                 ? ((JsonProcessingException) e).getOriginalMessage()
                 : e.getMessage();
     }

     private static void checkKeywordCase(String inputKeyword, String correctKeyword) throws DataModelParsingException {
         if (!correctKeyword.equals(inputKeyword)) {
             throw new DataModelParsingException("Keywords are case sensitive; the correct form is: "
                     + correctKeyword);
         }
     }

 }
	/*
	* 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.freemarker.onlinetester.util;

	import java.io.IOException;
	import java.io.StringReader;
	import java.math.BigDecimal;
	import java.sql.Time;
	import java.sql.Timestamp;
	import java.util.Collections;
	import java.util.LinkedHashMap;
	import java.util.List;
	import java.util.Map;
	import java.util.TimeZone;
	import java.util.regex.Matcher;
	import java.util.regex.Pattern;

	import javax.xml.parsers.DocumentBuilder;

	import org.apache.commons.lang3.StringUtils;
	import org.w3c.dom.Document;
	import org.xml.sax.ErrorHandler;
	import org.xml.sax.InputSource;
	import org.xml.sax.SAXException;

	import com.fasterxml.jackson.core.JsonProcessingException;
	import com.fasterxml.jackson.databind.ObjectMapper;

	import freemarker.ext.dom.NodeModel;
	import freemarker.template.utility.DateUtil;
	import freemarker.template.utility.DateUtil.CalendarFieldsToDateConverter;
	import freemarker.template.utility.DateUtil.DateParseException;
	import freemarker.template.utility.DateUtil.TrivialCalendarFieldsToDateConverter;

	/**
	* Parses the text that the user enters into the data model input field.
	*/
	public final class DataModelParser {

	private static final String KEYWORD_NEGATIVE_INFINITY = "-Infinity";

	private static final String KEYWORD_POSITIVE_INFINITY = "+Infinity";

	private static final String KEYWORD_INFINITY = "Infinity";

	private static final String KEYWORD_TRUE = "true";

	private static final String KEYWORD_FALSE = "false";

	private static final String KEYWORD_NULL = "null";

	private static final String KEYWORD_NAN = "NaN";

	/** Matches a line starting like "someVariable=". */
	private static final Pattern ASSIGNMENT_START = Pattern.compile(
	"^\\s*"
	+ "(\\p{L}[\\p{L}\\p{N}\\.:\\-_$@]*)" // name
	+ "[ \t]=\\s",
	Pattern.MULTILINE);

	/** Matches a value that starts like a number, or probably meant to be number at least. */
	private static final Pattern NUMBER_LIKE = Pattern.compile("[+-]?[\\.,]?[0-9].*", Pattern.DOTALL);

	private static final ObjectMapper JSON_MAPPER = new ObjectMapper();

	private DataModelParser() {
	// Not meant to be instantiated
	}

	public static Map<String, Object> parse(String src, TimeZone timeZone) throws DataModelParsingException {
	if (StringUtils.isBlank(src)) {
	return Collections.emptyMap();
	}

	Map<String, Object> dataModel = new LinkedHashMap<>();

	String lastName = null;
	int lastAssignmentStartEnd = 0;
	final Matcher assignmentStart = ASSIGNMENT_START.matcher(src);
	findAssignments: while (true) {
	boolean hasNextAssignment = assignmentStart.find(lastAssignmentStartEnd);

	if (lastName != null) {
	String value = src.substring(
	lastAssignmentStartEnd, hasNextAssignment ? assignmentStart.start() : src.length())
	.trim();
	final Object parsedValue;
	try {
	parsedValue = parseValue(value, timeZone);
	} catch (DataModelParsingException e) {
	throw new DataModelParsingException(
	"Failed to parse the value of \"" + lastName + "\":\n" + e.getMessage(), e.getCause());
	}
	dataModel.put(lastName, parsedValue);
	}

	if (lastName == null && (!hasNextAssignment \|\| assignmentStart.start() != 0)) {
	throw new DataModelParsingException(
	"The data model specification must start with an assignment (name=value).");
	}

	if (!hasNextAssignment) {
	break findAssignments;
	}

	lastName = assignmentStart.group(1).trim();
	lastAssignmentStartEnd = assignmentStart.end();
	}

	return dataModel;
	}

	private static Object parseValue(String value, TimeZone timeZone) throws DataModelParsingException {
	// Note: Because we fall back to interpret the input as a literal string value when it doesn't look like
	// anything else (like a number, boolean, etc.), it's important to avoid misunderstandings, and throw exception
	// in suspicious situations. The user can always quote the string value if we are "too smart". But he will
	// be confused about the rules of FreeMarker if what he believes to be a non-string is misinterpreted by this
	// parser as a string. Getting sometimes an error and then quoting the string is better than that.

	if (value.endsWith(";")) { // Tolerate this habit of Java and JavaScript programmers
	value = value.substring(value.length() - 1).trim();
	}

	if (NUMBER_LIKE.matcher(value).matches()) {
	try {
	return new BigDecimal(value);
	} catch (NumberFormatException e) {
	// Maybe it's a ISO 8601 Date/time/datetime
	CalendarFieldsToDateConverter calToDateConverter = new TrivialCalendarFieldsToDateConverter();

	DateParseException attemptedTemportalPExc = null;
	String attemptedTemporalType = null;
	final int dashIdx = value.indexOf('-');
	final int colonIdx = value.indexOf(':');
	if (value.indexOf('T') > 1 \|\| (dashIdx > 1 && colonIdx > dashIdx)) {
	try {
	return new Timestamp(
	DateUtil.parseISO8601DateTime(value, timeZone, calToDateConverter).getTime());
	} catch (DateParseException pExc) {
	attemptedTemporalType = "date-time";
	attemptedTemportalPExc = pExc;
	}
	} else if (dashIdx > 1) {
	try {
	return new java.sql.Date(
	DateUtil.parseISO8601Date(value, timeZone, calToDateConverter).getTime());
	} catch (DateParseException pExc) {
	attemptedTemporalType = "date";
	attemptedTemportalPExc = pExc;
	}
	} else if (colonIdx > 1) {
	try {
	return new Time(
	DateUtil.parseISO8601Time(value, timeZone, calToDateConverter).getTime());
	} catch (DateParseException pExc) {
	attemptedTemporalType = "time";
	attemptedTemportalPExc = pExc;
	}
	}
	if (attemptedTemportalPExc == null) {
	throw new DataModelParsingException("Malformed number: " + value, e);
	} else {
	throw new DataModelParsingException(
	"Malformed ISO 8601 " + attemptedTemporalType + " (or malformed number): " +
	attemptedTemportalPExc.getMessage(), e.getCause());
	}
	}
	} else if (value.startsWith("\"")) {
	try {
	return JSON_MAPPER.readValue(value, String.class);
	} catch (IOException e) {
	throw new DataModelParsingException(
	"Malformed quoted string (using JSON syntax): " + getMessageWithoutLocation(e),
	e);
	}
	} else if (value.startsWith("\'")) {
	throw new DataModelParsingException(
	"Malformed quoted string (using JSON syntax): Use \" character for quotation, not \' character.");
	} else if (value.startsWith("[")) {
	try {
	return JSON_MAPPER.readValue(value, List.class);
	} catch (IOException e) {
	throw new DataModelParsingException(
	"Malformed list (using JSON syntax): " + getMessageWithoutLocation(e),
	e);
	}
	} else if (value.startsWith("{")) {
	try {
	return JSON_MAPPER.readValue(value, LinkedHashMap.class);
	} catch (IOException e) {
	throw new DataModelParsingException(
	"Malformed list (using JSON syntax): " + getMessageWithoutLocation(e),
	e);
	}
	} else if (value.startsWith("<")) {
	try {
	DocumentBuilder builder = NodeModel.getDocumentBuilderFactory().newDocumentBuilder();
	ErrorHandler errorHandler = NodeModel.getErrorHandler();
	if (errorHandler != null) builder.setErrorHandler(errorHandler);
	final Document doc = builder.parse(new InputSource(new StringReader(value)));
	NodeModel.simplify(doc);
	return doc;
	} catch (SAXException e) {
	final String saxMsg = e.getMessage();
	throw new DataModelParsingException("Malformed XML: " + (saxMsg != null ? saxMsg : e), e);
	} catch (Exception e) {
	throw new DataModelParsingException("XML parsing has failed with internal error: " + e, e);
	}
	} else if (value.equalsIgnoreCase(KEYWORD_TRUE)) {
	checkKeywordCase(value, KEYWORD_TRUE);
	return Boolean.TRUE;
	} else if (value.equalsIgnoreCase(KEYWORD_FALSE)) {
	checkKeywordCase(value, KEYWORD_FALSE);
	return Boolean.FALSE;
	} else if (value.equalsIgnoreCase(KEYWORD_NULL)) {
	checkKeywordCase(value, KEYWORD_NULL);
	return null;
	} else if (value.equalsIgnoreCase(KEYWORD_NAN)) {
	checkKeywordCase(value, KEYWORD_NAN);
	return Double.NaN;
	} else if (value.equalsIgnoreCase(KEYWORD_INFINITY)) {
	checkKeywordCase(value, KEYWORD_INFINITY);
	return Double.POSITIVE_INFINITY;
	} else if (value.equalsIgnoreCase(KEYWORD_POSITIVE_INFINITY)) {
	checkKeywordCase(value, KEYWORD_POSITIVE_INFINITY);
	return Double.POSITIVE_INFINITY;
	} else if (value.equalsIgnoreCase(KEYWORD_NEGATIVE_INFINITY)) {
	checkKeywordCase(value, KEYWORD_NEGATIVE_INFINITY);
	return Double.NEGATIVE_INFINITY;
	} else if (value.length() == 0) {
	throw new DataModelParsingException(
	"Empty value. (If you indeed wanted a 0 length string, quote it, like \"\".)");
	} else {
	return value;
	}
	}

	private static String getMessageWithoutLocation(IOException e) {
	return e instanceof JsonProcessingException
	? ((JsonProcessingException) e).getOriginalMessage()
	: e.getMessage();
	}

	private static void checkKeywordCase(String inputKeyword, String correctKeyword) throws DataModelParsingException {
	if (!correctKeyword.equals(inputKeyword)) {
	throw new DataModelParsingException("Keywords are case sensitive; the correct form is: "
	+ correctKeyword);
	}
	}

	}