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<title>The Java Language Specification The Package java.lang </title>
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<center><h1>20.4 The Class <code>java.lang.Boolean</code></h1></center>
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Objects of type <code>Boolean</code> represent primitive values of type <code>boolean</code>.
<p><pre><a name="13812"></a>public final class <code><b>Boolean</b></code> {
<a name="3330"></a> public static final Boolean <code><b>TRUE</b></code> = new Boolean(true);
<a name="1888"></a> public static final Boolean <code><b>FALSE</b></code> = new Boolean(false);
<a name="1890"></a> public <code><b>Boolean</b></code>(boolean value);
<a name="1892"></a> public <code><b>Boolean</b></code>(String s);
<a name="1896"></a> public String <code><b>toString</b></code>();
<a name="1897"></a> public boolean <code><b>equals</b></code>(Object obj);
<a name="1902"></a> public int <code><b>hashCode</b></code>();
<a name="1905"></a> public boolean <code><b>booleanValue</b></code>();
<a name="1983"></a> public static Boolean <code><b>valueOf</b></code>(String s);
<a name="1984"></a> public static boolean <code><b>getBoolean</b></code>(String name);
<a name="1988"></a>}
</pre><a name="1985"></a>
<p><font size=+1><strong>20.4.1 </strong> <code>public static final Boolean <code><b>TRUE</b></code> = new Boolean(true);</code></font>
<p>
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The constant value of this field is a <code>Boolean</code> object corresponding to the primitive
value <code>true</code>.
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<p><font size=+1><strong>20.4.2 </strong> <code>public static final Boolean <code><b>FALSE</b></code> = new Boolean(false);</code></font>
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The constant value of this field is a <code>Boolean</code> object corresponding to the primitive
value <code>false</code>.
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<p><font size=+1><strong>20.4.3 </strong> <code>public <code><b>Boolean</b></code>(boolean value)</code></font>
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This constructor initializes a newly created <code>Boolean</code> object so that it represents
the primitive value that is the argument.
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<p><font size=+1><strong>20.4.4 </strong> <code>public <code><b>Boolean</b></code>(String s)</code></font>
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This constructor initializes a newly created <code>Boolean</code> object so that it represents
<code>true</code> if and only if the argument is not <code>null</code> and is equal, ignoring case, to the
string <code>"true"</code>.
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Examples:<p>
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<code>new</code> <code>Boolean("True")</code> produces a <code>Boolean</code> object that represents <code>true</code>.
<a name="1975"></a><code>new</code> <code>Boolean("yes")</code> produces a <code>Boolean</code> object that represents <code>false</code>.
</pre><a name="4068"></a>
<p><font size=+1><strong>20.4.5 </strong> <code>public String <code><b>toString</b></code>()</code></font>
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If this <code>Boolean</code> object represents <code>true</code>, a string equal to <code>"true"</code> is returned. If
this <code>Boolean</code> object represents <code>false</code>, a string equal to <code>"false"</code> is returned.
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Overrides the <code>toString</code> method of <code>Object</code> <a href="javalang.doc1.html#1152">(§20.1.2)</a>.<p>
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<p><font size=+1><strong>20.4.6 </strong> <code>public boolean <code><b>equals</b></code>(Object obj)</code></font>
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The result is <code>true</code> if and only if the argument is not <code>null</code> and is a <code>Boolean</code> object
that represents the same <code>boolean</code> value as this <code>Boolean</code> object.
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Overrides the <code>equals</code> method of <code>Object</code> <a href="javalang.doc1.html#14865">(§20.1.3)</a>.<p>
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<p><font size=+1><strong>20.4.7 </strong> <code>public int <code><b>hashCode</b></code>()</code></font>
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If this <code>Boolean</code> object represents <code>true</code>, the integer <code>1231</code> is returned. If this
<code>Boolean</code>  object represents <code>false</code>, the integer <code>1237</code> is returned.
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Overrides the <code>hashCode</code> method of <code>Object</code> <a href="javalang.doc1.html#13784">(§20.1.4)</a>.<p>
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<p><font size=+1><strong>20.4.8 </strong> <code>public boolean <code><b>booleanValue</b></code>()</code></font>
<p>
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The primitive <code>boolean</code> value represented by this <code>Boolean</code> object is returned.
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<p><font size=+1><strong>20.4.9 </strong> <code>public static boolean <code><b>valueOf</b></code>(String s)</code></font>
<p>
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The result is <code>true</code> if and only if the argument is not <code>null</code> and is equal, ignoring
case, to the string <code>"true"</code>.
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Example: <code>Boolean.valueOf("True")</code> returns <code>true</code>.<p>
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Example: <code>Boolean.valueOf("yes")</code> returns <code>false</code>.<p>
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<p><font size=+1><strong>20.4.10 </strong> <code>public static boolean <code><b>getBoolean</b></code>(String name)</code></font>
<p>
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The result is <code>true</code> if and only if the value of the system property (§20.18.9)</a> named
by the argument is equal, ignoring case, to the string <code>"true"</code>.<img src="javalang.doc.anc46.gif">
<p>
<hr>
<!-- This inserts footnotes--><p>
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<font size=-1>Java Language Specification (HTML generated by Suzette Pelouch on February 24, 1998)<br>
<i><a href="jcopyright.doc.html">Copyright © 1996 Sun Microsystems, Inc.</a>
All rights reserved</i>
<br>
Please send any comments or corrections to <a href="mailto:doug.kramer@sun.com">doug.kramer@sun.com</a>
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