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<link rel="stylesheet" type="text/css" href="../stylesheets/style.css">
<title>Echo Task</title>
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<body>

<h2 id="echo">Echo</h2>
<h3>Description</h3>
<p>Echoes a message to the current loggers and listeners which means <code>System.out</code> unless
overridden. A <var>level</var> can be specified, which controls at what logging level the message is
filtered at.</p>
<p>The task can also echo to a file, in which case the option to append rather than overwrite the
file is available, and the <var>level</var> option is ignored</p>
<h3>Parameters</h3>
<table class="attr">
  <tr>
    <th scope="col">Attribute</th>
    <th scope="col">Description</th>
    <th scope="col">Required</th>
  </tr>
  <tr>
    <td>message</td>
    <td>the message to echo.</td>
    <td>No; defaults to a blank line unless text is included in a character section within this
      element</td>
  </tr>
  <tr>
    <td>file</td>
    <td>the file to write the message to.</td>
    <td rowspan="2">No; only one of these may be used</td>
  </tr>
  <tr>
    <td>output</td>
    <td class="left">the <a href="../Types/resources.html">Resource</a>
      to write the message to (see <a href="../develop.html#set-magic">note</a>).
      <em>Since Apache Ant 1.8</em></td>
  </tr>
  <tr>
    <td>append</td>
    <td>Append to an existing file
      (or <a href="https://docs.oracle.com/javase/8/docs/api//java/io/FileWriter.html#FileWriter-java.lang.String-boolean-"
      target="_top"> open a new file / overwrite an existing file</a>)?
    </td>
    <td>No; ignored unless <var>output</var> indicates a filesystem destination, default
      is <q>false</q></td>
  </tr>
  <tr>
    <td>level</td>
    <td>Control the level at which this message is reported.  One
      of <q>error</q>, <q>warning</q>, <q>info</q>, <q>verbose</q>, <q>debug</q> (decreasing
      order)</td>
    <td>No; default is <q>warning</q></td>
  </tr>
  <tr>
    <td>encoding</td>
    <td>encoding to use. <em>since Ant 1.7</em></td>
    <td>No; defaults to default JVM character encoding</td>
  </tr>
  <tr>
    <td>force</td>
    <td>Overwrite read-only destination files.  <em>since Ant 1.8.2</em></td>
    <td>No; defaults to <q>false</q></td>
  </tr>
</table>

<h3>Examples</h3>

<p>Basic use:</p>
<pre>&lt;echo message=&quot;Hello, world&quot;/&gt;</pre>
<pre>&lt;echo message=&quot;Embed a line break:${line.separator}&quot;/&gt;</pre>
<pre>&lt;echo&gt;Embed another:${line.separator}&lt;/echo&gt;</pre>
<pre>&lt;echo&gt;This is a longer message stretching over
two lines.
&lt;/echo&gt;</pre>

<p>The newline immediately following the <code>&lt;echo&gt;</code> tag is part of the
output. Newlines in character data within the content of an element are not discarded by XML
parsers.<br/>See <a href="https://www.w3.org/TR/xml/#sec-line-ends" target="_top">W3C Recommendation
26 November 2008 / End of Line handling</a> for more details.</p>
<pre>&lt;echo&gt;
This is a longer message stretching over
three lines; the first line is a blank
&lt;/echo&gt;</pre>

<p>A message which only appears in <kbd>-debug</kbd> mode.</p>
<pre>&lt;echo message=&quot;Deleting drive C:&quot; level=&quot;debug&quot;/&gt;</pre>

<p>A message which appears even in <kbd>-quiet</kbd> mode.</p>
<pre>&lt;echo level=&quot;error&quot;&gt;
Imminent failure in the antimatter containment facility.
Please withdraw to safe location at least 50km away.
&lt;/echo&gt;</pre>

<p>Generate a shell script by echoing to a file.  Note the use of a double <q>$</q> symbol to stop
Ant filtering out the single <q>$</q> during variable expansion.</p>
<pre>&lt;echo file="runner.csh" append="false"&gt;#\!/bin/tcsh
java-1.3.1 -mx1024m ${project.entrypoint} $$*
&lt;/echo&gt;</pre>

<p>Depending on the log level Ant runs at, messages are print out or silently ignored:</p>
<table>
<tr>
  <th scope="col">Ant command line</th>
  <th scope="col"><kbd>-quiet</kbd>, <kbd>-q</kbd></th>
  <th scope="col"><em>no switch</em></th>
  <th scope="col"><kbd>-verbose</kbd>, <kbd>-v</kbd></th>
  <th scope="col"><kbd>-debug</kbd>, <kbd>-d</kbd></th>
</tr>
<tr>
  <td><pre>&lt;echo message="This is error message." level="error"/&gt;</pre></td>
  <td>ok</td>
  <td>ok</td>
  <td>ok</td>
  <td>ok</td>
</tr>
<tr>
  <td><pre>&lt;echo message="This is warning message."/&gt;</pre></td>
  <td>ok</td>
  <td>ok</td>
  <td>ok</td>
  <td>ok</td>
</tr>
<tr>
  <td><pre>&lt;echo message="This is warning message." level="warning"/&gt;</pre></td>
  <td>ok</td>
  <td>ok</td>
  <td>ok</td>
  <td>ok</td>
</tr>
<tr>
  <td><pre>&lt;echo message="This is info message." level="info"/&gt;</pre></td>
  <td>not logged</td>
  <td>ok</td>
  <td>ok</td>
  <td>ok</td>
</tr>
<tr>
  <td><pre>&lt;echo message="This is verbose message." level="verbose"/&gt;</pre></td>
  <td>not logged</td>
  <td>not logged</td>
  <td>ok</td>
  <td>ok</td>
</tr>
<tr>
  <td><pre>&lt;echo message="This is debug message." level="debug"/&gt;</pre></td>
  <td>not logged</td>
  <td>not logged</td>
  <td>not logged</td>
  <td>ok</td>
</tr>
</table>

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