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A remote dynamic Command pattern with GWT and LinkSet

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19 Jan 2011LGPL32 min read 16.5K   214   3  
Command pattern is a very useful solution, but it causes some problems when used in a distributed environment.
 
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MethodPointer (LinkSet Library 1.2-beta API)
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org.linkset</FONT>
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Class MethodPointer</H2>
<PRE>
java.lang.Object
  <IMG SRC="../../resources/inherit.gif" ALT="extended by "><B>org.linkset.MethodPointer</B>
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<DL>
<DT><PRE>public final class <B>MethodPointer</B><DT>extends java.lang.Object</DL>
</PRE>

<P>
The pointer to a listener
<P>

<P>
<DL>
<DT><B>Author:</B></DT>
  <DD>Lukasz Bownik (lukasz.bownik@gmail.com)</DD>
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<TD><CODE><B><A HREF="../../org/linkset/MethodPointer.html#MethodPointer(java.lang.Object, java.lang.String)">MethodPointer</A></B>(java.lang.Object&nbsp;target,
              java.lang.String&nbsp;methodId)</CODE>

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Contructor</TD>
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<CODE>&nbsp;boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../org/linkset/MethodPointer.html#equals(java.lang.Object)">equals</A></B>(java.lang.Object&nbsp;obj)</CODE>

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<CODE>&nbsp;int</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../org/linkset/MethodPointer.html#hashCode()">hashCode</A></B>()</CODE>

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<CODE>&nbsp;java.lang.Object</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../org/linkset/MethodPointer.html#invoke()">invoke</A></B>()</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;This method is equivalent to invoke((Object[])null);</TD>
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<CODE>&nbsp;java.lang.Object</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../org/linkset/MethodPointer.html#invoke(java.lang.Object[])">invoke</A></B>(java.lang.Object[]&nbsp;args)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Exerutes a method pointed by this pointer</TD>
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<CODE>&nbsp;java.lang.String</CODE></FONT></TD>
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<TD><CODE>clone, finalize, getClass, notify, notifyAll, wait, wait, wait</CODE></TD>
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<A NAME="MethodPointer(java.lang.Object, java.lang.String)"><!-- --></A><H3>
MethodPointer</H3>
<PRE>
public <B>MethodPointer</B>(java.lang.Object&nbsp;target,
                     java.lang.String&nbsp;methodId)</PRE>
<DL>
<DD>Contructor
<P>
<DL>
<DT><B>Parameters:</B><DD><CODE>methodId</CODE> - an id of a handler method
<DT><B>Throws:</B>
<DD><CODE>java.lang.NullPointerException</CODE> - id methodId == null or target == null
<DD><CODE>java.lang.IllegalArgumentException</CODE> - if methodId is empty</DL>
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<A NAME="toString()"><!-- --></A><H3>
toString</H3>
<PRE>
public java.lang.String <B>toString</B>()</PRE>
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<DT><B>Overrides:</B><DD><CODE>toString</CODE> in class <CODE>java.lang.Object</CODE></DL>
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<DT><B>See Also:</B><DD><CODE>Object.toString()</CODE></DL>
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<A NAME="hashCode()"><!-- --></A><H3>
hashCode</H3>
<PRE>
public int <B>hashCode</B>()</PRE>
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<DD><DL>
<DT><B>Overrides:</B><DD><CODE>hashCode</CODE> in class <CODE>java.lang.Object</CODE></DL>
</DD>
<DD><DL>
<DT><B>See Also:</B><DD><CODE>Object.hashCode()</CODE></DL>
</DD>
</DL>
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<A NAME="equals(java.lang.Object)"><!-- --></A><H3>
equals</H3>
<PRE>
public boolean <B>equals</B>(java.lang.Object&nbsp;obj)</PRE>
<DL>
<DD><DL>
<DT><B>Overrides:</B><DD><CODE>equals</CODE> in class <CODE>java.lang.Object</CODE></DL>
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<DT><B>See Also:</B><DD><CODE>Object.equals(Object)</CODE></DL>
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<A NAME="invoke(java.lang.Object[])"><!-- --></A><H3>
invoke</H3>
<PRE>
public java.lang.Object <B>invoke</B>(java.lang.Object[]&nbsp;args)
                        throws java.lang.reflect.InvocationTargetException,
                               java.lang.ExceptionInInitializerError</PRE>
<DL>
<DD>Exerutes a method pointed by this pointer
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>args</CODE> - method arguments
<DT><B>Returns:</B><DD>value returned by a called method or null
<DT><B>Throws:</B>
<DD><CODE>java.lang.ExceptionInInitializerError</CODE> - if the initialization provoked by this method fails.
<DD><CODE>java.lang.reflect.InvocationTargetException</CODE> - if the underlying method throws an exception.</DL>
</DD>
</DL>
<HR>

<A NAME="invoke()"><!-- --></A><H3>
invoke</H3>
<PRE>
public java.lang.Object <B>invoke</B>()
                        throws java.lang.reflect.InvocationTargetException,
                               java.lang.ExceptionInInitializerError</PRE>
<DL>
<DD>This method is equivalent to invoke((Object[])null);
<P>
<DD><DL>

<DT><B>Throws:</B>
<DD><CODE>java.lang.reflect.InvocationTargetException</CODE>
<DD><CODE>java.lang.ExceptionInInitializerError</CODE><DT><B>See Also:</B><DD><A HREF="../../org/linkset/MethodPointer.html#invoke(java.lang.Object[])"><CODE>invoke(java.lang.Object[])</CODE></A></DL>
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Written By
Łukasz Bownik
Architect
Poland Poland
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Posted 19 Jan 2011

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