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Collections2 (Google Collections Library 1.0-rc5)
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com.google.common.collect</FONT>
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Class Collections2</H2>
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<A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">java.lang.Object</A>
<IMG SRC="../../../../resources/inherit.gif" ALT="extended by "><B>com.google.common.collect.Collections2</B>
</PRE>
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<DL>
<DT><PRE>public final class <B>Collections2</B><DT>extends <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A></DL>
</PRE>
<P>
Provides static methods for working with <code>Collection</code> instances.
<P>
<P>
<DL>
<DT><B>Author:</B></DT>
<DD>Chris Povirk, Mike Bostock, Jared Levy</DD>
</DL>
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<P>
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<B>Method Summary</B></FONT></TH>
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<CODE>static
<TABLE BORDER="0" CELLPADDING="0" CELLSPACING="0" SUMMARY="">
<TR ALIGN="right" VALIGN="">
<TD NOWRAP><FONT SIZE="-1">
<CODE>&lt;E&gt; <A HREF="http://java.sun.com/javase/6/docs/api/java/util/Collection.html?is-external=true" title="class or interface in java.util">Collection</A>&lt;E&gt;</CODE></FONT></TD>
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</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../../com/google/common/collect/Collections2.html#filter(java.util.Collection, com.google.common.base.Predicate)">filter</A></B>(<A HREF="http://java.sun.com/javase/6/docs/api/java/util/Collection.html?is-external=true" title="class or interface in java.util">Collection</A>&lt;E&gt;&nbsp;unfiltered,
<A HREF="../../../../com/google/common/base/Predicate.html" title="interface in com.google.common.base">Predicate</A>&lt;? super E&gt;&nbsp;predicate)</CODE>
<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Returns the elements of <code>unfiltered</code> that satisfy a predicate.</TD>
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<CODE>static
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<CODE>&lt;F,T&gt; <A HREF="http://java.sun.com/javase/6/docs/api/java/util/Collection.html?is-external=true" title="class or interface in java.util">Collection</A>&lt;T&gt;</CODE></FONT></TD>
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</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../../com/google/common/collect/Collections2.html#transform(java.util.Collection, com.google.common.base.Function)">transform</A></B>(<A HREF="http://java.sun.com/javase/6/docs/api/java/util/Collection.html?is-external=true" title="class or interface in java.util">Collection</A>&lt;F&gt;&nbsp;fromCollection,
<A HREF="../../../../com/google/common/base/Function.html" title="interface in com.google.common.base">Function</A>&lt;? super F,T&gt;&nbsp;function)</CODE>
<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Returns a collection that applies <code>function</code> to each element of
<code>fromCollection</code>.</TD>
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<TH ALIGN="left"><B>Methods inherited from class java.lang.<A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A></B></TH>
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<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#clone()" title="class or interface in java.lang">clone</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#equals(java.lang.Object)" title="class or interface in java.lang">equals</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#finalize()" title="class or interface in java.lang">finalize</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#getClass()" title="class or interface in java.lang">getClass</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#hashCode()" title="class or interface in java.lang">hashCode</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#notify()" title="class or interface in java.lang">notify</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#notifyAll()" title="class or interface in java.lang">notifyAll</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#toString()" title="class or interface in java.lang">toString</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#wait()" title="class or interface in java.lang">wait</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#wait(long)" title="class or interface in java.lang">wait</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#wait(long, int)" title="class or interface in java.lang">wait</A></CODE></TD>
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<A NAME="filter(java.util.Collection, com.google.common.base.Predicate)"><!-- --></A><H3>
filter</H3>
<PRE>
public static &lt;E&gt; <A HREF="http://java.sun.com/javase/6/docs/api/java/util/Collection.html?is-external=true" title="class or interface in java.util">Collection</A>&lt;E&gt; <B>filter</B>(<A HREF="http://java.sun.com/javase/6/docs/api/java/util/Collection.html?is-external=true" title="class or interface in java.util">Collection</A>&lt;E&gt;&nbsp;unfiltered,
<A HREF="../../../../com/google/common/base/Predicate.html" title="interface in com.google.common.base">Predicate</A>&lt;? super E&gt;&nbsp;predicate)</PRE>
<DL>
<DD>Returns the elements of <code>unfiltered</code> that satisfy a predicate. The
returned collection is a live view of <code>unfiltered</code>; changes to one
affect the other.
<p>The resulting collection's iterator does not support <code>remove()</code>,
but all other collection methods are supported. The collection's
<code>add()</code> and <code>addAll()</code> methods throw an
<A HREF="http://java.sun.com/javase/6/docs/api/java/lang/IllegalArgumentException.html?is-external=true" title="class or interface in java.lang"><CODE>IllegalArgumentException</CODE></A> if an element that doesn't satisfy the
predicate is provided. When methods such as <code>removeAll()</code> and
<code>clear()</code> are called on the filtered collection, only elements that
satisfy the filter will be removed from the underlying collection.
<p>The returned collection isn't threadsafe or serializable, even if
<code>unfiltered</code> is.
<p>Many of the filtered collection's methods, such as <code>size()</code>,
iterate across every element in the underlying collection and determine
which elements satisfy the filter. When a live view is <i>not</i> needed,
it may be faster to copy <code>Iterables.filter(unfiltered, predicate)</code>
and use the copy.
<P>
<DD><DL>
</DL>
</DD>
</DL>
<HR>
<A NAME="transform(java.util.Collection, com.google.common.base.Function)"><!-- --></A><H3>
transform</H3>
<PRE>
public static &lt;F,T&gt; <A HREF="http://java.sun.com/javase/6/docs/api/java/util/Collection.html?is-external=true" title="class or interface in java.util">Collection</A>&lt;T&gt; <B>transform</B>(<A HREF="http://java.sun.com/javase/6/docs/api/java/util/Collection.html?is-external=true" title="class or interface in java.util">Collection</A>&lt;F&gt;&nbsp;fromCollection,
<A HREF="../../../../com/google/common/base/Function.html" title="interface in com.google.common.base">Function</A>&lt;? super F,T&gt;&nbsp;function)</PRE>
<DL>
<DD>Returns a collection that applies <code>function</code> to each element of
<code>fromCollection</code>. The returned collection is a live view of <code>fromCollection</code>; changes to one affect the other.
<p>The returned collection's <code>add()</code> and <code>addAll()</code> methods
throw an <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/UnsupportedOperationException.html?is-external=true" title="class or interface in java.lang"><CODE>UnsupportedOperationException</CODE></A>. All other collection
methods are supported, as long as <code>fromCollection</code> supports them.
<p>The returned collection isn't threadsafe or serializable, even if
<code>fromCollection</code> is.
<p>When a live view is <i>not</i> needed, it may be faster to copy the
transformed collection and use the copy.
<P>
<DD><DL>
</DL>
</DD>
</DL>
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