net.sf.jasperreports.engine.util.ExpressionParser Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of jasperreports Show documentation
Show all versions of jasperreports Show documentation
Free Java Reporting Library
/*
* JasperReports - Free Java Reporting Library.
* Copyright (C) 2001 - 2023 Cloud Software Group, Inc. All rights reserved.
* http://www.jaspersoft.com
*
* Unless you have purchased a commercial license agreement from Jaspersoft,
* the following license terms apply:
*
* This program is part of JasperReports.
*
* JasperReports is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* JasperReports is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with JasperReports. If not, see .
*/
package net.sf.jasperreports.engine.util;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import net.sf.jasperreports.engine.JRExpressionChunk;
import net.sf.jasperreports.engine.JRRuntimeException;
/**
*
* @author Lucian Chirita ([email protected])
*/
public class ExpressionParser
{
private static final ExpressionParser INSTANCE = new ExpressionParser();
public static ExpressionParser instance()
{
return INSTANCE;
}
public static final Pattern PLACEHOLDER_PATTERN =
Pattern.compile("\\$([RPFV])\\{(.*?)\\}", Pattern.MULTILINE | Pattern.DOTALL);
protected static final int PLACEHOLDER_TYPE_INDEX = 1;
protected static final int PLACEHOLDER_TEXT_INDEX = 2;
protected static final char PLACEHOLDER_START = '$';
protected static final char PLACEHOLDER_OPEN = '{';
protected static final char PLACEHOLDER_CLOSE = '}';
protected static final char PLACEHOLDER_TYPE_RESOURCE_MESSAGE = 'R';
protected static final char PLACEHOLDER_TYPE_PARAMETER = 'P';
protected static final char PLACEHOLDER_TYPE_FIELD = 'F';
protected static final char PLACEHOLDER_TYPE_VARIABLE = 'V';
public static interface ParseResult
{
void addTextChunk(String text);
void addChunk(byte chunkType, String chunkText);
}
public void parseExpression(String text, ParseResult result)
{
Matcher matcher = PLACEHOLDER_PATTERN.matcher(text);
int textChunkStart = 0;
StringBuilder textChunk = new StringBuilder(text.length());
while(matcher.find())
{
int matchStart = matcher.start();
int matchEnd = matcher.end();
if (matchStart > 0 && text.charAt(matchStart - 1) == '$')
{
// we have a $$ escape, append it to the text chunk with a single $
textChunk.append(text, textChunkStart, matchStart - 1);
textChunk.append(text, matchStart, matchEnd);
}
else
{
// we have a proper placeholder
textChunk.append(text, textChunkStart, matchStart);
if (textChunk.length() > 0)
{
result.addTextChunk(textChunk.toString());
textChunk.delete(0, textChunk.length());
}
String chunkStringType = matcher.group(PLACEHOLDER_TYPE_INDEX);
byte chunkType = chunkStringToType(chunkStringType);
String chunkText = matcher.group(PLACEHOLDER_TEXT_INDEX);
result.addChunk(chunkType, chunkText);
}
textChunkStart = matchEnd;
}
textChunk.append(text, textChunkStart, text.length());
if (textChunk.length() > 0)
{
result.addTextChunk(textChunk.toString());
}
}
protected byte chunkStringToType(String chunkStringType)
{
byte chunkType;
char firstChar = chunkStringType.charAt(0);
switch (firstChar)
{
case PLACEHOLDER_TYPE_PARAMETER:
chunkType = JRExpressionChunk.TYPE_PARAMETER;
break;
case PLACEHOLDER_TYPE_FIELD:
chunkType = JRExpressionChunk.TYPE_FIELD;
break;
case PLACEHOLDER_TYPE_VARIABLE:
chunkType = JRExpressionChunk.TYPE_VARIABLE;
break;
case PLACEHOLDER_TYPE_RESOURCE_MESSAGE:
chunkType = JRExpressionChunk.TYPE_RESOURCE;
break;
default:
throw
new JRRuntimeException(
JRExpressionUtil.EXCEPTION_MESSAGE_KEY_UNKNOWN_EXPRESSION_CHUNK_TYPE,
new Object[]{chunkStringType});
}
return chunkType;
}
public boolean fastPlaceholderDetect(String text)
{
int textLength = text.length();
int startIdx = text.indexOf(PLACEHOLDER_START);
boolean found = false;
while (startIdx >= 0)
{
if (startIdx + 3 >= textLength)
{
break;
}
char typeChart = text.charAt(startIdx + 1);
if ((typeChart == PLACEHOLDER_TYPE_RESOURCE_MESSAGE || typeChart == PLACEHOLDER_TYPE_PARAMETER
|| typeChart == PLACEHOLDER_TYPE_FIELD || typeChart == PLACEHOLDER_TYPE_VARIABLE)
&& text.charAt(startIdx + 2) == PLACEHOLDER_OPEN)
{
found = true;
break;
}
startIdx = text.indexOf(PLACEHOLDER_START, startIdx + 1);
}
return found;
}
}