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<TITLE>Enabling Assertions from the Command Line (Java Developers Almanac Example)
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<h3>e104. Enabling Assertions from the Command Line</h3>
The command line options <code>-ea</code> and <code>-da</code> allow you to enable and
disable assertion in a package subtree or in a class. Here are
several examples of the switches.
Enable assertions in all non-system classes:
<pre> java -ea <font color="#0066ff"><i>MyApp</i></font>
</pre>
Enable assertions in all classes in the unnamed package:
<pre> java -ea:... <font color="#0066ff"><i>MyApp</i></font>
</pre>
Enable assertions in all classes in a package subtree:
<pre> java -ea:<font color="#0066ff"><i>com.mycompany</i></font>... <font color="#0066ff"><i>MyApp</i></font>
</pre>
Enable assertions in a particular class:
<pre> java -ea:<font color="#0066ff"><i>com.mycompany.MyCompany</i></font> <font color="#0066ff"><i>MyApp</i></font>
</pre>
Disable assertions in all classes in a package subtree:
<pre> java -da:<font color="#0066ff"><i>com.mycompany</i></font>... <font color="#0066ff"><i>MyApp</i></font>
</pre>
Disable assertions in a particular class:
<pre> java -da:<font color="#0066ff"><i>com.mycompany.MyClass</i></font> <font color="#0066ff"><i>MyApp</i></font>
</pre>
Multiple assertion switches on the command line are processed
from left to right. Enable assertions in all classes in
a package subtree except for one class:
<pre> java -ea:<font color="#0066ff"><i>com.mycompany</i></font>... -da:<font color="#0066ff"><i>com.mycompany.MyClass</i></font> <font color="#0066ff"><i>MyApp</i></font>
</pre>
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<b>Related Examples</b></font></td>
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e103. <a class="eglink" href="assert_CompileAssert.html?l=rel">
Compiling a Program with Assertions
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e105. <a class="eglink" href="assert_AssertError.html?l=rel">
Handling an Assertion Error
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Arrays
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Classes
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Numbers
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Objects
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<a class="eglink" href="/egs/java.lang/pkg.html?l=rel#Strings">
Strings
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<a class="eglink" href="/egs/java.lang/pkg.html?l=rel#System%20Properties">
System Properties
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Threads
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