defaultexpression.html

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Gets the type of this expression.</TD>
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<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;<A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/geotools/filter/DefaultExpression.html#getValue(org.geotools.feature.Feature)">getValue</A></B>(<A HREF="../../../org/geotools/feature/Feature.html" title="interface in org.geotools.feature">Feature</A>&nbsp;feature)</CODE>

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<B>Deprecated.</B>&nbsp;<I>use <A HREF="../../../org/geotools/filter/DefaultExpression.html#evaluate(org.geotools.feature.Feature)"><CODE>evaluate(Feature)</CODE></A>.</I></TD>
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<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>protected static&nbsp;boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/geotools/filter/DefaultExpression.html#isAttributeExpression(short)">isAttributeExpression</A></B>(short&nbsp;expressionType)</CODE>

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Checks to see if passed type is attribute.</TD>
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<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>protected static&nbsp;boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/geotools/filter/DefaultExpression.html#isExpression(short)">isExpression</A></B>(short&nbsp;expressionType)</CODE>

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Checks to see if passed type is geometry.</TD>
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<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>static&nbsp;boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/geotools/filter/DefaultExpression.html#isFunctionExpression(short)">isFunctionExpression</A></B>(short&nbsp;expressionType)</CODE>

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<CODE>protected static&nbsp;boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/geotools/filter/DefaultExpression.html#isGeometryExpression(short)">isGeometryExpression</A></B>(short&nbsp;expressionType)</CODE>

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Checks to see if passed type is geometry.</TD>
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<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>protected static&nbsp;boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/geotools/filter/DefaultExpression.html#isLiteralExpression(short)">isLiteralExpression</A></B>(short&nbsp;expressionType)</CODE>

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Checks to see if passed type is geometry.</TD>
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<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>protected static&nbsp;boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/geotools/filter/DefaultExpression.html#isMathExpression(org.opengis.filter.expression.Expression)">isMathExpression</A></B>(Expression&nbsp;expression)</CODE>

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Checks to see if this expression is a math expresson based on its type.</TD>
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<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>protected static&nbsp;boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../org/geotools/filter/DefaultExpression.html#isMathExpression(short)">isMathExpression</A></B>(short&nbsp;expressionType)</CODE>

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<B>Deprecated.</B>&nbsp;<I>use <CODE>#is</CODE></I></TD>
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&nbsp;<A NAME="methods_inherited_from_class_ExpressionAbstract"><!-- --></A>
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<TD><B>Methods inherited from class <A HREF="../../../org/geotools/filter/expression/ExpressionAbstract.html" title="class in org.geotools.filter.expression">ExpressionAbstract</A></B></TD>
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<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="../../../org/geotools/filter/expression/ExpressionAbstract.html#accept(org.opengis.filter.expression.ExpressionVisitor, java.lang.Object)">accept</A>, <A HREF="../../../org/geotools/filter/expression/ExpressionAbstract.html#eval(org.geotools.filter.Expression, org.geotools.feature.Feature)">eval</A></CODE></TD>
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&nbsp;<A NAME="methods_inherited_from_class_Object"><!-- --></A>
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<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<TD><B>Methods inherited from class <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A></B></TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#clone()" title="class or interface in java.lang">clone</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#equals(java.lang.Object)" title="class or interface in java.lang">equals</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#finalize()" title="class or interface in java.lang">finalize</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#getClass()" title="class or interface in java.lang">getClass</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#hashCode()" title="class or interface in java.lang">hashCode</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#notify()" title="class or interface in java.lang">notify</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#notifyAll()" title="class or interface in java.lang">notifyAll</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#toString()" title="class or interface in java.lang">toString</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#wait()" title="class or interface in java.lang">wait</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#wait(long)" title="class or interface in java.lang">wait</A>, <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html#wait(long, int)" title="class or interface in java.lang">wait</A></CODE></TD>
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&nbsp;<A NAME="methods_inherited_from_class_Expression"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<TD><B>Methods inherited from interface Expression</B></TD>
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<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE>accept</CODE></TD>
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<!-- ============ FIELD DETAIL =========== -->

<A NAME="field_detail"><!-- --></A>
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<B>Field Detail</B></FONT></TD>
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<A NAME="expressionType"><!-- --></A><H3>
expressionType</H3>
<PRE>
protected short <B>expressionType</B></PRE>
<DL>
<DD>Defines the type of this expression.
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<DL>
</DL>
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<A NAME="permissiveConstruction"><!-- --></A><H3>
permissiveConstruction</H3>
<PRE>
protected boolean <B>permissiveConstruction</B></PRE>
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<DD>Defines the type of this expression.
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<DL>
</DL>
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<!-- ========= CONSTRUCTOR DETAIL ======== -->

<A NAME="constructor_detail"><!-- --></A>
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<B>Constructor Detail</B></FONT></TD>
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<A NAME="DefaultExpression()"><!-- --></A><H3>
DefaultExpression</H3>
<PRE>
public <B>DefaultExpression</B>()</PRE>
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<!-- ============ METHOD DETAIL ========== -->

<A NAME="method_detail"><!-- --></A>
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<B>Method Detail</B></FONT></TD>
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<A NAME="getType()"><!-- --></A><H3>
getType</H3>
<PRE>
public short <B>getType</B>()</PRE>
<DL>
<DD>Gets the type of this expression.
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<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../org/geotools/filter/Expression.html#getType()">getType</A></CODE> in interface <CODE><A HREF="../../../org/geotools/filter/Expression.html" title="interface in org.geotools.filter">Expression</A></CODE></DL>
</DD>
<DD><DL>

<DT><B>Returns:</B><DD>The short representation of the expression type.</DL>
</DD>
</DL>
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<A NAME="getValue(org.geotools.feature.Feature)"><!-- --></A><H3>
getValue</H3>
<PRE>
public final <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A> <B>getValue</B>(<A HREF="../../../org/geotools/feature/Feature.html" title="interface in org.geotools.feature">Feature</A>&nbsp;feature)</PRE>
<DL>
<DD><B>Deprecated.</B>&nbsp;<I>use <A HREF="../../../org/geotools/filter/DefaultExpression.html#evaluate(org.geotools.feature.Feature)"><CODE>evaluate(Feature)</CODE></A>.</I>
<P>
<DD>This method calls <A HREF="../../../org/geotools/filter/DefaultExpression.html#evaluate(org.geotools.feature.Feature)"><CODE>evaluate(Feature)</CODE></A>.
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../org/geotools/filter/Expression.html#getValue(org.geotools.feature.Feature)">getValue</A></CODE> in interface <CODE><A HREF="../../../org/geotools/filter/Expression.html" title="interface in org.geotools.filter">Expression</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>feature</CODE> - Specified feature to use when returning value.   Some
        expressions, such as LiteralExpressions, may ignore this as it
        does not affect their return value.
<DT><B>Returns:</B><DD>Value of the expression, evaluated with the feature object if
         necessary.</DL>
</DD>
</DL>
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<A NAME="evaluate(org.geotools.feature.Feature)"><!-- --></A><H3>
evaluate</H3>
<PRE>
public <A HREF="http://java.sun.com/j2se/1.4/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A> <B>evaluate</B>(<A HREF="../../../org/geotools/feature/Feature.html" title="interface in org.geotools.feature">Feature</A>&nbsp;feature)</PRE>
<DL>
<DD>Returns a value for this expression.  If the expression is an attribute
 expression then the attribute of the feature should be returned.  If a
 literal then the feature is ignored, the literal is returned as it has
 no relation to the feature.
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../org/geotools/filter/Expression.html#evaluate(org.geotools.feature.Feature)">evaluate</A></CODE> in interface <CODE><A HREF="../../../org/geotools/filter/Expression.html" title="interface in org.geotools.filter">Expression</A></CODE><DT><B>Overrides:</B><DD><CODE><A HREF="../../../org/geotools/filter/expression/ExpressionAbstract.html#evaluate(org.geotools.feature.Feature)">evaluate</A></CODE> in class <CODE><A HREF="../../../org/geotools/filter/expression/ExpressionAbstract.html" title="class in org.geotools.filter.expression">ExpressionAbstract</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>feature</CODE> - Specified feature to use when returning value.
<DT><B>Returns:</B><DD>The value of this expression based on the feature.<DT><B>'TODO:'</B></DT>
  <DD>REVISIT: make abstract?</DD>
</DL>
</DD>
</DL>
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<A NAME="evaluate(java.lang.Object)"><!-- --></A><H3>
evaluate</H3>