/*
 
* Copyright (c) 1999, 2018, Oracle and/or its affiliates. All rights reserved.
 
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 
*
 
* This code is free software; you can redistribute it and/or modify it
 
* under the terms of the GNU General Public License version 2 only, as
 
* published by the Free Software Foundation.
  
Oracle designates this
 
* particular file as subject to the "Classpath" exception as provided
 
* by Oracle in the LICENSE file that accompanied this code.
 
*
 
* This code 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
 
* version 2 for more details (a copy is included in the LICENSE file that
 
* accompanied this code).
 
*
 
* You should have received a copy of the GNU General Public License version
 
* 2 along with this work; if not, write to the Free Software Foundation,
 
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 
*
 
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 
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*/

package java.util.regex;

/**
 
* Unchecked exception thrown to indicate a syntax error in a
 
* regular-expression pattern.
 
*
 
* @author
  
unascribed
 
* @since 1.4
 
* @spec JSR-51
 
*/


public class PatternSyntaxException
    
extends IllegalArgumentException
{
    
private static final long serialVersionUID = -3864639126226059218L;

    
private final String desc;
    
private final String pattern;
    
private final int index;

    
/**
     
* Constructs a new instance of this class.
     
*
     
* @param
  
desc
     
*
         
A description of the error
     
*
     
* @param
  
regex
     
*
         
The erroneous pattern
     
*
     
* @param
  
index
     
*
         
The approximate index in the pattern of the error,
     
*
         
or {@code -1} if the index is not known
     
*/

    
public PatternSyntaxException(String desc, String regex, int index) {
        
this.desc = desc;
        
this.pattern = regex;
        
this.index = index;
    
}

    
/**
     
* Retrieves the error index.
     
*
     
* @return
  
The approximate index in the pattern of the error,
     
*
         
or {@code -1} if the index is not known
     
*/

    
public int getIndex() {
        
return index;
    
}

    
/**
     
* Retrieves the description of the error.
     
*
     
* @return
  
The description of the error
     
*/

    
public String getDescription() {
        
return desc;
    
}

    
/**
     
* Retrieves the erroneous regular-expression pattern.
     
*
     
* @return
  
The erroneous pattern
     
*/

    
public String getPattern() {
        
return pattern;
    
}

    
/**
     
* Returns a multi-line string containing the description of the syntax
     
* error and its index, the erroneous regular-expression pattern, and a
     
* visual indication of the error index within the pattern.
     
*
     
* @return
  
The full detail message
     
*/

    
public String getMessage() {
        
StringBuilder sb = new StringBuilder();
        
sb.append(desc);
        
if (index >= 0) {
            
sb.append(" near index ");
            
sb.append(index);
        
}
        
sb.append(System.lineSeparator());
        
sb.append(pattern);
        
if (index >= 0 && pattern != null && index < pattern.length()) {
            
sb.append(System.lineSeparator());
            
for (int i = 0; i < index; i++) sb.append(' ');
            
sb.append('^');
        
}
        
return sb.toString();
    
}

}