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Spring Cloud Contract Shaded Dependencies
package org.codehaus.plexus.interpolation;
/*
* Copyright 2001-2008 Codehaus Foundation.
*
* Licensed 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.
*/
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.WeakHashMap;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.codehaus.plexus.interpolation.util.StringUtils;
/**
* Expansion of the original RegexBasedInterpolator, found in plexus-utils, this
* interpolator provides options for setting custom prefix/suffix regex parts,
* and includes a {@link RecursionInterceptor} parameter in its interpolate(..)
* call, to allow the detection of cyclical expression references.
*
* @version $Id$
*/
public class RegexBasedInterpolator
implements Interpolator
{
private String startRegex;
private String endRegex;
private Map existingAnswers = new HashMap();
private List valueSources = new ArrayList();
private List postProcessors = new ArrayList();
private boolean reusePatterns = false;
private boolean cacheAnswers = false;
public static final String DEFAULT_REGEXP = "\\$\\{(.+?)\\}";
/**
* the key is the regex the value is the Pattern
* At the class construction time the Map will contains the default Pattern
*/
private Map compiledPatterns = new WeakHashMap();
/**
* Setup a basic interpolator.
*
* NOTE: You will have to call
* {@link RegexBasedInterpolator#addValueSource(ValueSource)} at least once
* if you use this constructor!
*/
public RegexBasedInterpolator()
{
compiledPatterns.put( DEFAULT_REGEXP, Pattern.compile( DEFAULT_REGEXP ) );
}
/**
* @param reusePatterns already compiled patterns will be reused
*/
public RegexBasedInterpolator( boolean reusePatterns )
{
this();
this.reusePatterns = reusePatterns;
}
/**
* Setup an interpolator with no value sources, and the specified regex pattern
* prefix and suffix in place of the default one.
*
* NOTE: You will have to call
* {@link RegexBasedInterpolator#addValueSource(ValueSource)} at least once
* if you use this constructor!
*
* @param startRegex start of the regular expression to use
* @param endRegex end of the regular expression to use
*/
public RegexBasedInterpolator (String startRegex, String endRegex)
{
this();
this.startRegex = startRegex;
this.endRegex = endRegex;
}
/**
* Setup a basic interpolator with the specified list of value sources.
*
* @param valueSources The list of value sources to use
*/
public RegexBasedInterpolator( List valueSources )
{
this();
this.valueSources.addAll( valueSources );
}
/**
* Setup an interpolator with the specified value sources, and the specified
* regex pattern prefix and suffix in place of the default one.
*
* @param startRegex start of the regular expression to use
* @param endRegex end of the regular expression to use
* @param valueSources The list of value sources to use
*/
public RegexBasedInterpolator (String startRegex, String endRegex, List valueSources )
{
this();
this.startRegex = startRegex;
this.endRegex = endRegex;
this.valueSources.addAll( valueSources );
}
/**
* {@inheritDoc}
*/
public void addValueSource( ValueSource valueSource )
{
valueSources.add( valueSource );
}
/**
* {@inheritDoc}
*/
public void removeValuesSource( ValueSource valueSource )
{
valueSources.remove( valueSource );
}
/**
* {@inheritDoc}
*/
public void addPostProcessor( InterpolationPostProcessor postProcessor )
{
postProcessors.add( postProcessor );
}
/**
* {@inheritDoc}
*/
public void removePostProcessor( InterpolationPostProcessor postProcessor )
{
postProcessors.remove( postProcessor );
}
/**
* Attempt to resolve all expressions in the given input string, using the
* given pattern to first trim an optional prefix from each expression. The
* supplied recursion interceptor will provide protection from expression
* cycles, ensuring that the input can be resolved or an exception is
* thrown.
*
* @param input The input string to interpolate
*
* @param thisPrefixPattern An optional pattern that should be trimmed from
* the start of any expressions found in the input.
*
* @param recursionInterceptor Used to protect the interpolation process
* from expression cycles, and throw an
* exception if one is detected.
*/
public String interpolate( String input,
String thisPrefixPattern,
RecursionInterceptor recursionInterceptor )
throws InterpolationException
{
if (input == null )
{
// return empty String to prevent NPE too
return "";
}
if ( recursionInterceptor == null )
{
recursionInterceptor = new SimpleRecursionInterceptor();
}
if ( thisPrefixPattern != null && thisPrefixPattern.length() == 0 )
{
thisPrefixPattern = null;
}
int realExprGroup = 2;
Pattern expressionPattern;
if ( startRegex != null || endRegex != null )
{
if ( thisPrefixPattern == null )
{
expressionPattern = getPattern( startRegex + endRegex );
realExprGroup = 1;
}
else
{
expressionPattern = getPattern( startRegex + thisPrefixPattern + endRegex );
}
}
else if ( thisPrefixPattern != null )
{
expressionPattern = getPattern( "\\$\\{(" + thisPrefixPattern + ")?(.+?)\\}" );
}
else
{
expressionPattern = getPattern( DEFAULT_REGEXP );
realExprGroup = 1;
}
try
{
return interpolate( input, recursionInterceptor, expressionPattern, realExprGroup );
}
finally
{
if ( !cacheAnswers )
{
clearAnswers();
}
}
}
private Pattern getPattern( String regExp )
{
if ( !reusePatterns )
{
return Pattern.compile( regExp );
}
Pattern pattern;
synchronized( this )
{
pattern = compiledPatterns.get( regExp );
if ( pattern != null )
{
return pattern;
}
pattern = Pattern.compile( regExp );
compiledPatterns.put( regExp, pattern );
}
return pattern;
}
/**
* Entry point for recursive resolution of an expression and all of its
* nested expressions.
*
* @todo Ensure unresolvable expressions don't trigger infinite recursion.
*/
private String interpolate( String input,
RecursionInterceptor recursionInterceptor,
Pattern expressionPattern,
int realExprGroup )
throws InterpolationException
{
if (input == null )
{
// return empty String to prevent NPE too
return "";
}
String result = input;
Matcher matcher = expressionPattern.matcher( result );
while ( matcher.find() )
{
String wholeExpr = matcher.group( 0 );
String realExpr = matcher.group( realExprGroup );
if ( realExpr.startsWith( "." ) )
{
realExpr = realExpr.substring( 1 );
}
if ( recursionInterceptor.hasRecursiveExpression( realExpr ) )
{
throw new InterpolationCycleException( recursionInterceptor, realExpr, wholeExpr );
}
recursionInterceptor.expressionResolutionStarted( realExpr );
try
{
Object value = existingAnswers.get( realExpr );
for ( ValueSource vs : valueSources )
{
if (value != null) break;
value = vs.getValue( realExpr );
}
if ( value != null )
{
value =
interpolate( String.valueOf( value ), recursionInterceptor, expressionPattern, realExprGroup );
if ( postProcessors != null && !postProcessors.isEmpty() )
{
for ( InterpolationPostProcessor postProcessor : postProcessors )
{
Object newVal = postProcessor.execute( realExpr, value );
if ( newVal != null )
{
value = newVal;
break;
}
}
}
// could use:
// result = matcher.replaceFirst( stringValue );
// but this could result in multiple lookups of stringValue, and replaceAll is not correct behaviour
result = StringUtils.replace( result, wholeExpr, String.valueOf( value ) );
matcher.reset( result );
}
}
finally
{
recursionInterceptor.expressionResolutionFinished( realExpr );
}
}
return result;
}
/**
* Return any feedback messages and errors that were generated - but
* suppressed - during the interpolation process. Since unresolvable
* expressions will be left in the source string as-is, this feedback is
* optional, and will only be useful for debugging interpolation problems.
*
* @return a {@link List} that may be interspersed with {@link String} and
* {@link Throwable} instances.
*/
public List getFeedback()
{
List messages = new ArrayList();
for ( Object valueSource : valueSources )
{
ValueSource vs = (ValueSource) valueSource;
List feedback = vs.getFeedback();
if ( feedback != null && !feedback.isEmpty() )
{
messages.addAll( feedback );
}
}
return messages;
}
/**
* Clear the feedback messages from previous interpolate(..) calls.
*/
public void clearFeedback()
{
for ( Object valueSource : valueSources )
{
ValueSource vs = (ValueSource) valueSource;
vs.clearFeedback();
}
}
/**
* See {@link RegexBasedInterpolator#interpolate(String, String, RecursionInterceptor)}.
*
* This method triggers the use of a {@link SimpleRecursionInterceptor}
* instance for protection against expression cycles.
*
* @param input The input string to interpolate
*
* @param thisPrefixPattern An optional pattern that should be trimmed from
* the start of any expressions found in the input.
*/
public String interpolate( String input,
String thisPrefixPattern )
throws InterpolationException
{
return interpolate( input, thisPrefixPattern, null );
}
/**
* See {@link RegexBasedInterpolator#interpolate(String, String, RecursionInterceptor)}.
*
* This method triggers the use of a {@link SimpleRecursionInterceptor}
* instance for protection against expression cycles. It also leaves empty the
* expression prefix which would otherwise be trimmed from expressions. The
* result is that any detected expression will be resolved as-is.
*
* @param input The input string to interpolate
*/
public String interpolate( String input )
throws InterpolationException
{
return interpolate( input, null, null );
}
/**
* See {@link RegexBasedInterpolator#interpolate(String, String, RecursionInterceptor)}.
*
* This method leaves empty the expression prefix which would otherwise be
* trimmed from expressions. The result is that any detected expression will
* be resolved as-is.
*
* @param input The input string to interpolate
*
* @param recursionInterceptor Used to protect the interpolation process
* from expression cycles, and throw an
* exception if one is detected.
*/
public String interpolate( String input,
RecursionInterceptor recursionInterceptor )
throws InterpolationException
{
return interpolate( input, null, recursionInterceptor );
}
public boolean isReusePatterns()
{
return reusePatterns;
}
public void setReusePatterns( boolean reusePatterns )
{
this.reusePatterns = reusePatterns;
}
public boolean isCacheAnswers()
{
return cacheAnswers;
}
public void setCacheAnswers( boolean cacheAnswers )
{
this.cacheAnswers = cacheAnswers;
}
public void clearAnswers()
{
existingAnswers.clear();
}
}