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/*
* 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.
*
*/
/**
* Various string manipulation methods that are more efficient then chaining
* string operations: all is done in the same buffer without creating a bunch of
* string objects.
*
* @author <a href="mailto:dev@labs.apache.org">Dungeon Project</a>
*/
public class Main {
/**
* A deep trim of a string remove whitespace from the ends as well as
* excessive whitespace within the inside of the string between
* non-whitespace characters. A deep trim reduces internal whitespace down
* to a single space to perserve the whitespace separated tokenization order
* of the String.
*
* @param string
* the string to deep trim.
* @return the trimmed string.
*/
public static final String deepTrim( String string )
{
return deepTrim( string, false );
}
/**
* This does the same thing as a trim but we also lowercase the string while
* performing the deep trim within the same buffer. This saves us from
* having to create multiple String and StringBuffer objects and is much
* more efficient.
*
* @see StringTools#deepTrim( String )
*/
public static final String deepTrimToLower( String string )
{
return deepTrim( string, true );
}
/**
* Put common code to deepTrim(String) and deepTrimToLower here.
*
* @param str
* the string to deep trim
* @param toLowerCase
* how to normalize for case: upper or lower
* @return the deep trimmed string
* @see StringTools#deepTrim( String )
*
* TODO Replace the toCharArray() by substring manipulations
*/
public static final String deepTrim( String str, boolean toLowerCase )
{
if ( ( null == str ) || ( str.length() == 0 ) )
{
return "";
}
char ch;
char[] buf = str.toCharArray();
char[] newbuf = new char[buf.length];
boolean wsSeen = false;
boolean isStart = true;
int pos = 0;
for ( int i = 0; i < str.length(); i++ )
{
ch = buf[i];
// filter out all uppercase characters
if ( toLowerCase )
{
if ( Character.isUpperCase( ch ) )
{
ch = Character.toLowerCase( ch );
}
}
// Check to see if we should add space
if ( Character.isWhitespace( ch ) )
{
// If the buffer has had characters added already check last
// added character. Only append a spc if last character was
// not whitespace.
if ( wsSeen )
{
continue;
}
else
{
wsSeen = true;
if ( isStart )
{
isStart = false;
}
else
{
newbuf[pos++] = ch;
}
}
}
else
{
// Add all non-whitespace
wsSeen = false;
isStart = false;
newbuf[pos++] = ch;
}
}
return ( pos == 0 ? "" : new String( newbuf, 0, ( wsSeen ? pos - 1 : pos ) ) );
}
}
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