youys
/
ant

 
			
							<!--
   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.
-->
<html>

<head>
<meta http-equiv="Content-Language" content="en-us">
<link rel="stylesheet" type="text/css" href="../stylesheets/style.css">
<title>Echoproperties Task</title>
</head>

<body>

<h2><a name="echoproperties">echoproperties</a></h2>
<h3>Description</h3>

<p>Displays all the current properties (or a subset of them specified
by a nested <code>&lt;propertyset&gt;</code>) in the project.  The
output can be sent to a file if desired.  This task can be used as a
somewhat contrived means of returning data from an
<tt>&lt;ant&gt;</tt> invocation, but is really for debugging build
files.</p>

<h3>Parameters</h3>
<table border="1" cellpadding="2" cellspacing="0">
  <tr>
    <td valign="top"><b>Attribute</b></td>
    <td valign="top"><b>Description</b></td>
    <td align="center" valign="top"><b>Required</b></td>
  </tr>
  <tr>
    <td valign="top">destfile</td>
    <td valign="top">If specified, the value indicates the name of the
    file to send the output of the statement to.  The generated output file
    is compatible for loading by any Java application as a property file.
    If not specified, then the output will go to the Apache Ant log.</td>
    <td valign="top" align="center">No</td>
  </tr>
  <tr>
    <td valign="top">prefix</td>
    <td valign="top">
        a prefix which is used to filter the properties
        only those properties starting with this prefix will be echoed.
        <P>
    </td>
    <td valign="top" align="center">No</td>
  </tr>
  <tr>
    <td valign="top">regex</td>
    <td valign="top">
        a regular expression which is used to filter the
        properties
        only those properties whose names match it will be echoed.
    </td>
    <td valign="top" align="center">No</td>
  </tr>   
  <tr>
    <td valign="top">failonerror</td>
    <td valign="top">By default, the "failonerror" attribute is enabled.
    If an error occurs while writing the properties to a file, and this
    attribute is enabled, then a BuildException will be thrown, causing the
    build to fail.  If disabled, then IO errors will be reported as a log
    statement, and the build will continue without failure from this task.</td>
    <td valign="top" align="center">No</td>
  </tr>
  <tr>
    <td valign="top">format</td>
    <td valign="top">One of <code>text</code> or <code>xml</code>.
    Determines the output format.  Defaults to <code>text</code>.</td>
    <td valign="top" align="center">No</td>
  </tr>
</table>

<h3>Parameters specified as nested elements</h3>

<h4>propertyset</h4>

<p>You can specify subsets of properties to be echoed with <a
href="../Types/propertyset.html">propertyset</a>s. Using
<tt>propertyset</tt>s gives more control on which properties will be
picked up. The attributes <tt>prefix</tt> and <tt>regex</tt> are just
shortcuts that use <tt>propertyset</tt>s internally.
</p>

<p><em>since Ant 1.6</em>.</p>

<h3>Examples</h3>
<blockquote><pre>
  &lt;echoproperties/&gt;
</pre></blockquote>
<p>Report the current properties to the log.</p>
<blockquote><pre>
  &lt;echoproperties destfile="my.properties"/&gt;
</pre></blockquote>
<p>Report the current properties to the file "my.properties", and will
fail the build if the file could not be created or written to.</p>
<blockquote><pre>
  &lt;echoproperties destfile="my.properties" failonerror="false"/&gt;
</pre></blockquote>
<p>Report the current properties to the file "my.properties", and will
log a message if the file could not be created or written to, but will still
allow the build to continue.</p>
<blockquote><pre>
  &lt;echoproperties prefix="java."/&gt;
</pre></blockquote>
<p>List all properties beginning with "java."</p>
<blockquote><pre>
  &lt;echoproperties&gt;
    &lt;propertyset&gt;
      &lt;propertyref prefix="java."/&gt;
    &lt;/propertyset&gt;
  &lt;/echoproperties&gt;
</pre></blockquote>
<p>This again lists all properties beginning with "java." using a nested
<tt>&lt;/propertyset&gt;</tt> which is an equivalent but longer way.</p>
<blockquote><pre>
  &lt;echoproperties regex=".*ant.*"/&gt;
</pre></blockquote>
<p>Lists all properties that contain "ant" in their names.
The equivalent snippet with <tt>&lt;/propertyset&gt;</tt> is:</p>
<blockquote><pre>
  &lt;echoproperties&gt;
    &lt;propertyset&gt;
      &lt;propertyref regex=".*ant.*"/&gt;
    &lt;/propertyset&gt;
  &lt;/echoproperties&gt;
</pre></blockquote>


</body>
</html>