Start line:  
End line:  

Snippet Preview

Snippet HTML Code

Stack Overflow Questions
   * Copyright (c) 2003 The Visigoth Software Society. All rights
   * reserved.
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in
  *    the documentation and/or other materials provided with the
  *    distribution.
  * 3. The end-user documentation included with the redistribution, if
  *    any, must include the following acknowledgement:
  *       "This product includes software developed by the
  *        Visigoth Software Society ("
  *    Alternately, this acknowledgement may appear in the software itself,
  *    if and wherever such third-party acknowledgements normally appear.
  * 4. Neither the name "FreeMarker", "Visigoth", nor any of the names of the 
  *    project contributors may be used to endorse or promote products derived
  *    from this software without prior written permission. For written
  *    permission, please contact
  * 5. Products derived from this software may not be called "FreeMarker" or "Visigoth"
  *    nor may "FreeMarker" or "Visigoth" appear in their names
  *    without prior written permission of the Visigoth Software Society.
  * ====================================================================
  * This software consists of voluntary contributions made by many
  * individuals on behalf of the Visigoth Software Society. For more
  * information on the Visigoth Software Society, please see
 package freemarker.template.utility;
 import java.util.*;

Gives FreeMarker the the ability to execute external commands. Will fork a process, and inline anything that process sends to stdout in the template. Based on a patch submitted by Peter Molettiere.

BE CAREFUL! this tag, depending on use, may allow you to set something up so that users of your web application could run arbitrary code on your server. This can only happen if you allow unchecked GET/POST submissions to be used as the command string in the exec tag.

From java:

 SimpleHash root = new SimpleHash();

 root.put( "exec", new freemarker.template.utility.Execute() );


From your FreeMarker template:

 The following is executed:
 ${exec( "/usr/bin/ls" )}


$Id:,v 1.14 2003/10/13 11:57:18 szegedia Exp $
 public class Execute implements freemarker.template.TemplateMethodModel {
     private final static int OUTPUT_BUFFER_SIZE = 1024;

Executes a method call.

arguments a List of String objects containing the values of the arguments passed to the method.
the TemplateModel produced by the method, or null.
    public Object exec (List argumentsthrows TemplateModelException {
        String aExecute;
        StringBuffer    aOutputBuffer = new StringBuffer();
        ifarguments.size() < 1 ) {
            throw new TemplateModelException"Need an argument to execute" );
        aExecute = (String)(arguments.get(0));
        try {
            Process exec = Runtime.getRuntime().execaExecute );
            // stdout from the process comes in here
            InputStream execOut = exec.getInputStream();
            Reader execReader = new InputStreamReaderexecOut );
            char[] buffer = new char ];
            int bytes_read = execReader.readbuffer );
            whilebytes_read > 0 ) {
                aOutputBuffer.appendbuffer, 0, bytes_read );
                bytes_read = execReader.readbuffer );
        catchIOException ioe ) {
            throw new TemplateModelExceptionioe.getMessage() );
        return aOutputBuffer.toString();
New to GrepCode? Check out our FAQ X