src/main/java/org/apache/maven/shared/filtering/InterpolatorFilterReaderLineEnding.java - maven-filtering - Git at Google

 package org.apache.maven.shared.filtering;

 /*
  * 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.
  */

 import java.io.BufferedReader;
 import java.io.FilterReader;
 import java.io.IOException;
 import java.io.Reader;

 import org.codehaus.plexus.interpolation.InterpolationException;
 import org.codehaus.plexus.interpolation.Interpolator;
 import org.codehaus.plexus.interpolation.RecursionInterceptor;
 import org.codehaus.plexus.interpolation.SimpleRecursionInterceptor;

 /**
  * A FilterReader implementation, that works with Interpolator interface instead of it's own interpolation
  * implementation. This implementation is heavily based on org.codehaus.plexus.util.InterpolationFilterReader.
  *
  * @author cstamas
  * @author Olivier Lamy
  * @since 1.0
  */
 public class InterpolatorFilterReaderLineEnding
     extends FilterReader
 {

     /**
      * Interpolator used to interpolate
      */
     private Interpolator interpolator;

     private RecursionInterceptor recursionInterceptor;

     /**
      * replacement text from a token
      */
     private String replaceData = null;

     /**
      * Index into replacement data
      */
     private int replaceIndex = 0;

     /**
      * Default begin token.
      */
     public static final String DEFAULT_BEGIN_TOKEN = "${";

     /**
      * Default end token.
      */
     public static final String DEFAULT_END_TOKEN = "}";

     private String beginToken;

     private String endToken;

     /**
      * true by default to preserve backward comp
      */
     private boolean interpolateWithPrefixPattern = true;

     private String escapeString;

     private boolean useEscape = false;

     /**
      * if true escapeString will be preserved \{foo} -> \{foo}
      */
     private boolean preserveEscapeString = false;

     private boolean supportMultiLineFiltering;

     /**
      * must always be bigger than escape string plus delimiters, but doesn't need to be exact
      */
     private int markLength = 16;

     private boolean eof = false;

     /**
      * @param in reader to use
      * @param interpolator interpolator instance to use
      * @param beginToken start token to use
      * @param endToken end token to use
      * @param supportMultiLineFiltering If multi line filtering is allowed
      */
     public InterpolatorFilterReaderLineEnding( Reader in, Interpolator interpolator, String beginToken, String endToken,
                                                boolean supportMultiLineFiltering )
     {
         this( in, interpolator, beginToken, endToken, new SimpleRecursionInterceptor(), supportMultiLineFiltering );
     }

     /**
      * @param in reader to use
      * @param interpolator interpolator instance to use
      * @param beginToken start token to use
      * @param endToken end token to use
      * @param ri The {@link RecursionInterceptor} to use to prevent recursive expressions.
      * @param supportMultiLineFiltering If multi line filtering is allowed
      */
     private InterpolatorFilterReaderLineEnding( Reader in, Interpolator interpolator, String beginToken,
                                                 String endToken, RecursionInterceptor ri,
                                                 boolean supportMultiLineFiltering )
     {
         // wrap our own buffer, so we can use mark/reset safely.
         super( new BufferedReader( in ) );

         this.interpolator = interpolator;

         this.beginToken = beginToken;

         this.endToken = endToken;

         recursionInterceptor = ri;

         this.supportMultiLineFiltering = supportMultiLineFiltering;

         calculateMarkLength();

     }

     /**
      * Skips characters. This method will block until some characters are available, an I/O error occurs, or the end of
      * the stream is reached.
      *
      * @param n The number of characters to skip
      * @return the number of characters actually skipped
      * @throws IOException If an I/O error occurs
      */
     public long skip( long n )
         throws IOException
     {
         if ( n < 0L )
         {
             throw new IllegalArgumentException( "skip value is negative" );
         }

         for ( long i = 0; i < n; i++ )
         {
             if ( read() == -1 )
             {
                 return i;
             }
         }
         return n;
     }

     /**
      * Reads characters into a portion of an array. This method will block until some input is available, an I/O error
      * occurs, or the end of the stream is reached.
      *
      * @param cbuf Destination buffer to write characters to. Must not be <code>null</code>.
      * @param off Offset at which to start storing characters.
      * @param len Maximum number of characters to read.
      * @return the number of characters read, or -1 if the end of the stream has been reached
      * @throws IOException If an I/O error occurs
      */
     public int read( char cbuf[], int off, int len )
         throws IOException
     {
         for ( int i = 0; i < len; i++ )
         {
             int ch = read();
             if ( ch == -1 )
             {
                 if ( i == 0 )
                 {
                     return -1;
                 }
                 else
                 {
                     return i;
                 }
             }
             cbuf[off + i] = (char) ch;
         }
         return len;
     }

     /**
      * Returns the next character in the filtered stream, replacing tokens from the original stream.
      *
      * @return the next character in the resulting stream, or -1 if the end of the resulting stream has been reached
      * @throws IOException if the underlying stream throws an IOException during reading
      */
     public int read()
         throws IOException
     {
         if ( replaceIndex > 0 )
         {
             return replaceData.charAt( replaceData.length() - ( replaceIndex-- ) );
         }
         if ( eof )
         {
             return -1;
         }

         in.mark( markLength );

         int ch = in.read();
         if ( ( ch == -1 ) || ( ch == '\n' && !supportMultiLineFiltering ) )
         {
             return ch;
         }

         boolean inEscape = ( useEscape && ch == escapeString.charAt( 0 ) );

         StringBuilder key = new StringBuilder();

         // have we found an escape string?
         if ( inEscape )
         {
             for ( int i = 0; i < escapeString.length(); i++ )
             {
                 key.append( (char) ch );

                 if ( ch != escapeString.charAt( i ) || ch == -1 || ( ch == '\n' && !supportMultiLineFiltering ) )
                 {
                     // mismatch, EOF or EOL, no escape string here
                     in.reset();
                     inEscape = false;
                     key.setLength( 0 );
                     break;
                 }

                 ch = in.read();

             }

         }

         // have we found a delimiter?
         boolean foundToken = false;
         for ( int i = 0; i < beginToken.length(); i++ )
         {
             if ( ch != beginToken.charAt( i ) || ch == -1 || ( ch == '\n' && !supportMultiLineFiltering ) )
             {
                 // mismatch, EOF or EOL, no match
                 break;
             }

             if ( i == beginToken.length() - 1 )
             {

                 foundToken = true;

             }

             ch = in.read();

         }

         in.reset();
         in.skip( key.length() );
         ch = in.read();

         // escape means no luck, prevent parsing of the escaped character, and return
         if ( inEscape )
         {

             if ( beginToken != null )
             {
                 if ( !preserveEscapeString )
                 {
                     key.setLength( 0 );
                 }
             }

             key.append( (char) ch );

             replaceData = key.toString();
             replaceIndex = key.length();

             return read();

         }

         // no match means no luck, reset and return
         if ( !foundToken )
         {

             in.reset();
             return in.read();

         }

         // we're committed, find the end token, EOL or EOF

         key.append( beginToken );
         in.reset();
         in.skip( beginToken.length() );
         ch = in.read();

         int endTokenSize = endToken.length();
         int end = endTokenSize;
         do
         {
             if ( ch == -1 )
             {
                 break;
             }
             else if ( ch == '\n' && !supportMultiLineFiltering )
             {
                 // EOL
                 key.append( (char) ch );
                 break;
             }

             key.append( (char) ch );

             if ( ch == this.endToken.charAt( endTokenSize - end ) )
             {
                 end--;
                 if ( end == 0 )
                 {
                     break;
                 }
             }
             else
             {
                 end = endTokenSize;
             }

             ch = in.read();
         }
         while ( true );

         // found endtoken? interpolate our key resolved above
         String value = null;
         if ( end == 0 )
         {
             try
             {
                 if ( interpolateWithPrefixPattern )
                 {
                     value = interpolator.interpolate( key.toString(), "", recursionInterceptor );
                 }
                 else
                 {
                     value = interpolator.interpolate( key.toString(), recursionInterceptor );
                 }
             }
             catch ( InterpolationException e )
             {
                 IllegalArgumentException error = new IllegalArgumentException( e.getMessage() );
                 error.initCause( e );

                 throw error;
             }
         }

         // write away the value if present, otherwise the key unmodified
         if ( value != null )
         {
             replaceData = value;
             replaceIndex = value.length();
         }
         else
         {
             replaceData = key.toString();
             replaceIndex = key.length();
         }

         if ( ch == -1 )
         {
             eof = true;
         }
         return read();

     }

     /**
      * @return current state of interpolate with prefix pattern.
      */
     public boolean isInterpolateWithPrefixPattern()
     {
         return interpolateWithPrefixPattern;
     }

     /**
      * @param interpolateWithPrefixPattern interpolate with prefix pattern.
      */
     public void setInterpolateWithPrefixPattern( boolean interpolateWithPrefixPattern )
     {
         this.interpolateWithPrefixPattern = interpolateWithPrefixPattern;
     }

     /**
      * @return The current value of escapeString.
      */
     public String getEscapeString()
     {
         return escapeString;
     }

     /**
      * @param escapeString Set the value for escapeString.
      */
     public void setEscapeString( String escapeString )
     {
         // TODO NPE if escapeString is null ?
         if ( escapeString != null && escapeString.length() >= 1 )
         {
             this.escapeString = escapeString;
             this.useEscape = escapeString != null && escapeString.length() >= 1;
             calculateMarkLength();
         }
     }

     /**
      * @return state of preserve escape string.
      */
     public boolean isPreserveEscapeString()
     {
         return preserveEscapeString;
     }

     /**
      * @param preserveEscapeString {@link #preserveEscapeString}
      */
     public void setPreserveEscapeString( boolean preserveEscapeString )
     {
         this.preserveEscapeString = preserveEscapeString;
     }

     /**
      * @return {@link #recursionInterceptor}
      */
     public RecursionInterceptor getRecursionInterceptor()
     {
         return recursionInterceptor;
     }

     /**
      * @param theRecursionInterceptor {@link RecursionInterceptor}
      * @return {@link InterpolatorFilterReaderLineEnding}
      */
     public InterpolatorFilterReaderLineEnding setRecursionInterceptor( RecursionInterceptor theRecursionInterceptor )
     {
         this.recursionInterceptor = theRecursionInterceptor;
         return this;
     }

     private void calculateMarkLength()
     {
         markLength = 16;

         if ( escapeString != null )
         {
             markLength += escapeString.length();
         }

         if ( beginToken != null )
         {
             markLength += beginToken.length();
         }

         if ( endToken != null )
         {
             markLength += endToken.length();
         }

     }

 }
	package org.apache.maven.shared.filtering;

	/*
	* 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.
	*/

	import java.io.BufferedReader;
	import java.io.FilterReader;
	import java.io.IOException;
	import java.io.Reader;

	import org.codehaus.plexus.interpolation.InterpolationException;
	import org.codehaus.plexus.interpolation.Interpolator;
	import org.codehaus.plexus.interpolation.RecursionInterceptor;
	import org.codehaus.plexus.interpolation.SimpleRecursionInterceptor;

	/**
	* A FilterReader implementation, that works with Interpolator interface instead of it's own interpolation
	* implementation. This implementation is heavily based on org.codehaus.plexus.util.InterpolationFilterReader.
	*
	* @author cstamas
	* @author Olivier Lamy
	* @since 1.0
	*/
	public class InterpolatorFilterReaderLineEnding
	extends FilterReader
	{

	/**
	* Interpolator used to interpolate
	*/
	private Interpolator interpolator;

	private RecursionInterceptor recursionInterceptor;

	/**
	* replacement text from a token
	*/
	private String replaceData = null;

	/**
	* Index into replacement data
	*/
	private int replaceIndex = 0;

	/**
	* Default begin token.
	*/
	public static final String DEFAULT_BEGIN_TOKEN = "${";

	/**
	* Default end token.
	*/
	public static final String DEFAULT_END_TOKEN = "}";

	private String beginToken;

	private String endToken;

	/**
	* true by default to preserve backward comp
	*/
	private boolean interpolateWithPrefixPattern = true;

	private String escapeString;

	private boolean useEscape = false;

	/**
	* if true escapeString will be preserved \{foo} -> \{foo}
	*/
	private boolean preserveEscapeString = false;

	private boolean supportMultiLineFiltering;

	/**
	* must always be bigger than escape string plus delimiters, but doesn't need to be exact
	*/
	private int markLength = 16;

	private boolean eof = false;

	/**
	* @param in reader to use
	* @param interpolator interpolator instance to use
	* @param beginToken start token to use
	* @param endToken end token to use
	* @param supportMultiLineFiltering If multi line filtering is allowed
	*/
	public InterpolatorFilterReaderLineEnding( Reader in, Interpolator interpolator, String beginToken, String endToken,
	boolean supportMultiLineFiltering )
	{
	this( in, interpolator, beginToken, endToken, new SimpleRecursionInterceptor(), supportMultiLineFiltering );
	}

	/**
	* @param in reader to use
	* @param interpolator interpolator instance to use
	* @param beginToken start token to use
	* @param endToken end token to use
	* @param ri The {@link RecursionInterceptor} to use to prevent recursive expressions.
	* @param supportMultiLineFiltering If multi line filtering is allowed
	*/
	private InterpolatorFilterReaderLineEnding( Reader in, Interpolator interpolator, String beginToken,
	String endToken, RecursionInterceptor ri,
	boolean supportMultiLineFiltering )
	{
	// wrap our own buffer, so we can use mark/reset safely.
	super( new BufferedReader( in ) );

	this.interpolator = interpolator;

	this.beginToken = beginToken;

	this.endToken = endToken;

	recursionInterceptor = ri;

	this.supportMultiLineFiltering = supportMultiLineFiltering;

	calculateMarkLength();

	}

	/**
	* Skips characters. This method will block until some characters are available, an I/O error occurs, or the end of
	* the stream is reached.
	*
	* @param n The number of characters to skip
	* @return the number of characters actually skipped
	* @throws IOException If an I/O error occurs
	*/
	public long skip( long n )
	throws IOException
	{
	if ( n < 0L )
	{
	throw new IllegalArgumentException( "skip value is negative" );
	}

	for ( long i = 0; i < n; i++ )
	{
	if ( read() == -1 )
	{
	return i;
	}
	}
	return n;
	}

	/**
	* Reads characters into a portion of an array. This method will block until some input is available, an I/O error
	* occurs, or the end of the stream is reached.
	*
	* @param cbuf Destination buffer to write characters to. Must not be <code>null</code>.
	* @param off Offset at which to start storing characters.
	* @param len Maximum number of characters to read.
	* @return the number of characters read, or -1 if the end of the stream has been reached
	* @throws IOException If an I/O error occurs
	*/
	public int read( char cbuf[], int off, int len )
	throws IOException
	{
	for ( int i = 0; i < len; i++ )
	{
	int ch = read();
	if ( ch == -1 )
	{
	if ( i == 0 )
	{
	return -1;
	}
	else
	{
	return i;
	}
	}
	cbuf[off + i] = (char) ch;
	}
	return len;
	}

	/**
	* Returns the next character in the filtered stream, replacing tokens from the original stream.
	*
	* @return the next character in the resulting stream, or -1 if the end of the resulting stream has been reached
	* @throws IOException if the underlying stream throws an IOException during reading
	*/
	public int read()
	throws IOException
	{
	if ( replaceIndex > 0 )
	{
	return replaceData.charAt( replaceData.length() - ( replaceIndex-- ) );
	}
	if ( eof )
	{
	return -1;
	}

	in.mark( markLength );

	int ch = in.read();
	if ( ( ch == -1 ) \|\| ( ch == '\n' && !supportMultiLineFiltering ) )
	{
	return ch;
	}

	boolean inEscape = ( useEscape && ch == escapeString.charAt( 0 ) );

	StringBuilder key = new StringBuilder();

	// have we found an escape string?
	if ( inEscape )
	{
	for ( int i = 0; i < escapeString.length(); i++ )
	{
	key.append( (char) ch );

	if ( ch != escapeString.charAt( i ) \|\| ch == -1 \|\| ( ch == '\n' && !supportMultiLineFiltering ) )
	{
	// mismatch, EOF or EOL, no escape string here
	in.reset();
	inEscape = false;
	key.setLength( 0 );
	break;
	}

	ch = in.read();

	}

	}

	// have we found a delimiter?
	boolean foundToken = false;
	for ( int i = 0; i < beginToken.length(); i++ )
	{
	if ( ch != beginToken.charAt( i ) \|\| ch == -1 \|\| ( ch == '\n' && !supportMultiLineFiltering ) )
	{
	// mismatch, EOF or EOL, no match
	break;
	}

	if ( i == beginToken.length() - 1 )
	{

	foundToken = true;

	}

	ch = in.read();

	}

	in.reset();
	in.skip( key.length() );
	ch = in.read();

	// escape means no luck, prevent parsing of the escaped character, and return
	if ( inEscape )
	{

	if ( beginToken != null )
	{
	if ( !preserveEscapeString )
	{
	key.setLength( 0 );
	}
	}

	key.append( (char) ch );

	replaceData = key.toString();
	replaceIndex = key.length();

	return read();

	}

	// no match means no luck, reset and return
	if ( !foundToken )
	{

	in.reset();
	return in.read();

	}

	// we're committed, find the end token, EOL or EOF

	key.append( beginToken );
	in.reset();
	in.skip( beginToken.length() );
	ch = in.read();

	int endTokenSize = endToken.length();
	int end = endTokenSize;
	do
	{
	if ( ch == -1 )
	{
	break;
	}
	else if ( ch == '\n' && !supportMultiLineFiltering )
	{
	// EOL
	key.append( (char) ch );
	break;
	}

	key.append( (char) ch );

	if ( ch == this.endToken.charAt( endTokenSize - end ) )
	{
	end--;
	if ( end == 0 )
	{
	break;
	}
	}
	else
	{
	end = endTokenSize;
	}

	ch = in.read();
	}
	while ( true );

	// found endtoken? interpolate our key resolved above
	String value = null;
	if ( end == 0 )
	{
	try
	{
	if ( interpolateWithPrefixPattern )
	{
	value = interpolator.interpolate( key.toString(), "", recursionInterceptor );
	}
	else
	{
	value = interpolator.interpolate( key.toString(), recursionInterceptor );
	}
	}
	catch ( InterpolationException e )
	{
	IllegalArgumentException error = new IllegalArgumentException( e.getMessage() );
	error.initCause( e );

	throw error;
	}
	}

	// write away the value if present, otherwise the key unmodified
	if ( value != null )
	{
	replaceData = value;
	replaceIndex = value.length();
	}
	else
	{
	replaceData = key.toString();
	replaceIndex = key.length();
	}

	if ( ch == -1 )
	{
	eof = true;
	}
	return read();

	}

	/**
	* @return current state of interpolate with prefix pattern.
	*/
	public boolean isInterpolateWithPrefixPattern()
	{
	return interpolateWithPrefixPattern;
	}

	/**
	* @param interpolateWithPrefixPattern interpolate with prefix pattern.
	*/
	public void setInterpolateWithPrefixPattern( boolean interpolateWithPrefixPattern )
	{
	this.interpolateWithPrefixPattern = interpolateWithPrefixPattern;
	}

	/**
	* @return The current value of escapeString.
	*/
	public String getEscapeString()
	{
	return escapeString;
	}

	/**
	* @param escapeString Set the value for escapeString.
	*/
	public void setEscapeString( String escapeString )
	{
	// TODO NPE if escapeString is null ?
	if ( escapeString != null && escapeString.length() >= 1 )
	{
	this.escapeString = escapeString;
	this.useEscape = escapeString != null && escapeString.length() >= 1;
	calculateMarkLength();
	}
	}

	/**
	* @return state of preserve escape string.
	*/
	public boolean isPreserveEscapeString()
	{
	return preserveEscapeString;
	}

	/**
	* @param preserveEscapeString {@link #preserveEscapeString}
	*/
	public void setPreserveEscapeString( boolean preserveEscapeString )
	{
	this.preserveEscapeString = preserveEscapeString;
	}

	/**
	* @return {@link #recursionInterceptor}
	*/
	public RecursionInterceptor getRecursionInterceptor()
	{
	return recursionInterceptor;
	}

	/**
	* @param theRecursionInterceptor {@link RecursionInterceptor}
	* @return {@link InterpolatorFilterReaderLineEnding}
	*/
	public InterpolatorFilterReaderLineEnding setRecursionInterceptor( RecursionInterceptor theRecursionInterceptor )
	{
	this.recursionInterceptor = theRecursionInterceptor;
	return this;
	}

	private void calculateMarkLength()
	{
	markLength = 16;

	if ( escapeString != null )
	{
	markLength += escapeString.length();
	}

	if ( beginToken != null )
	{
	markLength += beginToken.length();
	}

	if ( endToken != null )
	{
	markLength += endToken.length();
	}

	}

	}