content: package com.japisoft.xmlpad.editor;
  
  import javax.swing.text.BadLocationException;
  
  import com.japisoft.xmlpad.editor.XMLEditor;
  
  /**
  This program is available under two licenses : 
  
  1. For non commercial usage : 
  
  This program is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.
  
  This program 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 General Public License for more details.
  
  You should have received a copy of the GNU General Public License
  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  
  2. For commercial usage :
  
  You need to get a commercial license for source usage at : 
  
  http://www.editix.com/buy.html
  
  Copyright (c) 2018 Alexandre Brillant - JAPISOFT SARL - http://www.japisoft.com
  
  @author Alexandre Brillant - abrillant@japisoft.com
  @author JAPISOFT SARL - http://www.japisoft.com
  
  */
  public class ExpressionHighlighterManager {
  
  	public static void highlight( XMLEditor editor ) {
  
  		// Remove the previous one
  		editor.removeHighlightExpression();
  
  		try {
  			String part = 
  				editor.getText( editor.getCaretPosition(), 1 );
  			char c = 
  				part.charAt( 0 );
  			
  			int searchDirection = +1;
  			char o = 0;
  
  			boolean beginPart = ( c == '<' || c == '(' || c == '{' || c == '[' );
  			if ( !beginPart ) {
  				part = editor.getText( editor.getCaretPosition() - 1, 1 );
  				c = part.charAt( 0 );
  			}
  			boolean endPart = ( c == '>' || c == ')' || c == '}' || c == ']' );
  			
  			int location = editor.getCaretPosition();
  						
  			if ( endPart ) {
  				searchDirection = -1;
  				if ( c == '>' )
  					o = '<';
  				else
  				if ( c == ')' )
  					o = '(';
  				else
  				if ( c == '}' )
  					o = '{';
  				else
  				if ( c == ']' )
  					o = '[';
  				location--;
  			} else
  			if ( beginPart ) {
  				if ( c == '<' )
  					o = '>';
  				else
  				if ( c == '(' )
  					o = ')';
  				else
  				if ( c == '{' )
  					o = '}';
  				else
  				if ( c == '[' )
  					o = ']';
  				location++;
  			} else
  				return;	// Nothing to check
  
  			int counter = 0;
  
  			for ( int i = 0; i < 1000; i++ ) {
  				
  				location += searchDirection;
  				String tmp = 
  					editor.getText( location, 1 );
  				
  				if ( tmp.charAt( 0 ) == c ) {
  					counter++;
  				}
  				
  				if ( tmp.charAt( 0 ) == o ) {
  					if ( counter == 0 ) {
  						
  						editor.highlightExpression( location );
  						
  						break;
  					}
  					counter--;
  				}
  				
  			}
  			
  		} catch ( BadLocationException e ) {
  		}
  		
  	}
  
  }
  