You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@velocity.apache.org by ge...@locus.apache.org on 2000/12/27 15:31:57 UTC
cvs commit: jakarta-velocity/src/java/org/apache/velocity/runtime/parser/node ASTAddNode.java ASTDivNode.java ASTModNode.java ASTMulNode.java ASTSubtractNode.java
geirm 00/12/27 06:31:56
Modified: src/java/org/apache/velocity/runtime/parser/node
ASTAddNode.java ASTDivNode.java ASTModNode.java
ASTMulNode.java ASTSubtractNode.java
Log:
A few things :
- Added checks to ensure that args to math ops are not null (catch those pesky NPE's)
- Put in log messages to tell user what is going on when math doesn't go as expected.
- Contrained math operations to integers only (for now).
- Did div0 checks for mod and division.
- Added license info.
Revision Changes Path
1.2 +113 -3 jakarta-velocity/src/java/org/apache/velocity/runtime/parser/node/ASTAddNode.java
Index: ASTAddNode.java
===================================================================
RCS file: /home/cvs/jakarta-velocity/src/java/org/apache/velocity/runtime/parser/node/ASTAddNode.java,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- ASTAddNode.java 2000/10/20 19:14:01 1.1
+++ ASTAddNode.java 2000/12/27 14:31:52 1.2
@@ -1,9 +1,76 @@
/* Generated By:JJTree: Do not edit this line. ASTAddNode.java */
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2000 The Apache Software Foundation. All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ * any, must include the following acknowlegement:
+ * "This product includes software developed by the
+ * Apache Software Foundation (http://www.apache.org/)."
+ * Alternately, this acknowlegement may appear in the software itself,
+ * if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
+ * Foundation" must not be used to endorse or promote products derived
+ * from this software without prior written permission. For written
+ * permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ * nor may "Apache" appear in their names without prior written
+ * permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation. For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+
+/**
+ * Handles integer addition of nodes
+ *
+ * Please look at the Parser.jjt file which is
+ * what controls the generation of this class.
+ *
+ * @author <a href="mailto:jvanzyl@periapt.com">Jason van Zyl</a>
+ * @author <a href="mailto:geirm@optonline.net">Geir Magnusson Jr.</a>
+ * @version $Id: ASTAddNode.java,v 1.2 2000/12/27 14:31:52 geirm Exp $
+*/
+
package org.apache.velocity.runtime.parser.node;
import org.apache.velocity.Context;
-import org.apache.velocity.runtime.parser.*;
+import org.apache.velocity.runtime.Runtime;
+import org.apache.velocity.runtime.parser.Parser;
public class ASTAddNode extends SimpleNode
{
@@ -23,10 +90,53 @@
return visitor.visit(this, data);
}
+ /**
+ * computes the sum of the two nodes. Currently only integer operations are
+ * supported.
+ * @return Integer object with value, or null
+ */
public Object value(Context context)
{
- return new Integer(((Integer) jjtGetChild(0).value(context)).intValue() +
- ((Integer) jjtGetChild(1).value(context)).intValue());
+ /*
+ * get the two addends
+ */
+
+ Object left = jjtGetChild(0).value( context );
+ Object right = jjtGetChild(1).value( context );
+
+ /*
+ * if either is null, lets log and bail
+ */
+
+ if (left == null || right == null)
+ {
+ Runtime.error( ( left == null ? "Left" : "Right" ) + " side of addition operation has null value."
+ + " Operation not possible. "
+ + context.getCurrentTemplateName() + " [line " + getLine()
+ + ", column " + getColumn() + "]");
+ return null;
+ }
+
+ /*
+ * if not an Integer, not much we can do either
+ */
+
+ if ( !( left instanceof Integer ) || !( right instanceof Integer ))
+ {
+ Runtime.error( ( !( left instanceof Integer ) ? "Left" : "Right" )
+ + " side of addition operation is not a valid type. "
+ + "Currently only integers (1,2,3...) and Integer type is supported. "
+ + context.getCurrentTemplateName() + " [line " + getLine()
+ + ", column " + getColumn() + "]");
+
+ return null;
+ }
+
+ return new Integer( ( (Integer) left ).intValue() + ( (Integer) right ).intValue() );
}
}
+
+
+
+
1.2 +122 -4 jakarta-velocity/src/java/org/apache/velocity/runtime/parser/node/ASTDivNode.java
Index: ASTDivNode.java
===================================================================
RCS file: /home/cvs/jakarta-velocity/src/java/org/apache/velocity/runtime/parser/node/ASTDivNode.java,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- ASTDivNode.java 2000/10/20 19:14:02 1.1
+++ ASTDivNode.java 2000/12/27 14:31:53 1.2
@@ -1,9 +1,76 @@
/* Generated By:JJTree: Do not edit this line. ASTDivNode.java */
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2000 The Apache Software Foundation. All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ * any, must include the following acknowlegement:
+ * "This product includes software developed by the
+ * Apache Software Foundation (http://www.apache.org/)."
+ * Alternately, this acknowlegement may appear in the software itself,
+ * if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
+ * Foundation" must not be used to endorse or promote products derived
+ * from this software without prior written permission. For written
+ * permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ * nor may "Apache" appear in their names without prior written
+ * permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation. For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+
+/**
+ * Handles integer division of nodes
+ *
+ * Please look at the Parser.jjt file which is
+ * what controls the generation of this class.
+ *
+ * @author <a href="mailto:jvanzyl@periapt.com">Jason van Zyl</a>
+ * @author <a href="mailto:geirm@optonline.net">Geir Magnusson Jr.</a>
+ * @version $Id: ASTDivNode.java,v 1.2 2000/12/27 14:31:53 geirm Exp $
+*/
+
package org.apache.velocity.runtime.parser.node;
import org.apache.velocity.Context;
-import org.apache.velocity.runtime.parser.*;
+import org.apache.velocity.runtime.Runtime;
+import org.apache.velocity.runtime.parser.Parser;
public class ASTDivNode extends SimpleNode
{
@@ -23,10 +90,61 @@
return visitor.visit(this, data);
}
+ /**
+ * computes the result of the division. Currently limited to
+ * Integers.
+ * @return Integer(value) or null
+ */
public Object value(Context context)
{
- return new Integer(((Integer) jjtGetChild(0).value(context)).intValue() /
- ((Integer) jjtGetChild(1).value(context)).intValue());
- }
+ /*
+ * get the two args
+ */
+
+ Object left = jjtGetChild(0).value( context );
+ Object right = jjtGetChild(1).value( context );
+
+ /*
+ * if either is null, lets log and bail
+ */
+
+ if (left == null || right == null)
+ {
+ Runtime.error( ( left == null ? "Left" : "Right" ) + " side of division operation has null value."
+ + " Operation not possible. "
+ + context.getCurrentTemplateName() + " [line " + getLine()
+ + ", column " + getColumn() + "]");
+ return null;
+ }
+
+ /*
+ * if not an Integer, not much we can do either
+ */
+
+ if ( !( left instanceof Integer ) || !( right instanceof Integer ))
+ {
+ Runtime.error( ( !( left instanceof Integer ) ? "Left" : "Right" )
+ + " side of division operation is not a valid type. "
+ + "Currently only integers (1,2,3...) and Integer type is supported. "
+ + context.getCurrentTemplateName() + " [line " + getLine()
+ + ", column " + getColumn() + "]");
+
+ return null;
+ }
+
+ /*
+ * check for divide by 0
+ */
+
+ if ( ( (Integer) right).intValue() == 0 )
+ {
+ Runtime.error( "Right side of division operation is zero. Must be non-zero. "
+ + context.getCurrentTemplateName() + " [line " + getLine()
+ + ", column " + getColumn() + "]");
+
+ return null;
+ }
+ return new Integer( ( (Integer) left ).intValue() / ( (Integer) right ).intValue() );
+ }
}
1.2 +122 -1 jakarta-velocity/src/java/org/apache/velocity/runtime/parser/node/ASTModNode.java
Index: ASTModNode.java
===================================================================
RCS file: /home/cvs/jakarta-velocity/src/java/org/apache/velocity/runtime/parser/node/ASTModNode.java,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- ASTModNode.java 2000/10/20 19:14:02 1.1
+++ ASTModNode.java 2000/12/27 14:31:53 1.2
@@ -1,8 +1,75 @@
/* Generated By:JJTree: Do not edit this line. ASTModNode.java */
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2000 The Apache Software Foundation. All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ * any, must include the following acknowlegement:
+ * "This product includes software developed by the
+ * Apache Software Foundation (http://www.apache.org/)."
+ * Alternately, this acknowlegement may appear in the software itself,
+ * if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
+ * Foundation" must not be used to endorse or promote products derived
+ * from this software without prior written permission. For written
+ * permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ * nor may "Apache" appear in their names without prior written
+ * permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation. For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+
+/**
+ * Handles integer modulus division
+ *
+ * Please look at the Parser.jjt file which is
+ * what controls the generation of this class.
+ *
+ * @author <a href="mailto:geirm@optonline.net">Geir Magnusson Jr.</a>
+ * @version $Id: ASTModNode.java,v 1.2 2000/12/27 14:31:53 geirm Exp $
+*/
+
package org.apache.velocity.runtime.parser.node;
-import org.apache.velocity.runtime.parser.*;
+import org.apache.velocity.Context;
+import org.apache.velocity.runtime.Runtime;
+import org.apache.velocity.runtime.parser.Parser;
public class ASTModNode extends SimpleNode
{
@@ -21,4 +88,58 @@
{
return visitor.visit(this, data);
}
+
+ public Object value(Context context)
+ {
+ /*
+ * get the two args
+ */
+
+ Object left = jjtGetChild(0).value( context );
+ Object right = jjtGetChild(1).value( context );
+
+ /*
+ * if either is null, lets log and bail
+ */
+
+ if (left == null || right == null)
+ {
+ Runtime.error( ( left == null ? "Left" : "Right" ) + " side of modulus operation has null value."
+ + " Operation not possible. "
+ + context.getCurrentTemplateName() + " [line " + getLine()
+ + ", column " + getColumn() + "]");
+ return null;
+ }
+
+ /*
+ * if not an Integer, not much we can do either
+ */
+
+ if ( !( left instanceof Integer ) || !( right instanceof Integer ))
+ {
+ Runtime.error( ( !( left instanceof Integer ) ? "Left" : "Right" )
+ + " side of modulus operation is not a valid type. "
+ + "Currently only integers (1,2,3...) and Integer type is supported. "
+ + context.getCurrentTemplateName() + " [line " + getLine()
+ + ", column " + getColumn() + "]");
+
+ return null;
+ }
+
+ /*
+ * check for divide by 0
+ */
+
+ if ( ( (Integer) right).intValue() == 0 )
+ {
+ Runtime.error( "Right side of modulus operation is zero. Must be non-zero. "
+ + context.getCurrentTemplateName() + " [line " + getLine()
+ + ", column " + getColumn() + "]");
+
+ return null;
+ }
+
+ return new Integer( ( (Integer) left ).intValue() % ( (Integer) right ).intValue() );
+ }
}
+
1.2 +111 -5 jakarta-velocity/src/java/org/apache/velocity/runtime/parser/node/ASTMulNode.java
Index: ASTMulNode.java
===================================================================
RCS file: /home/cvs/jakarta-velocity/src/java/org/apache/velocity/runtime/parser/node/ASTMulNode.java,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- ASTMulNode.java 2000/10/20 19:14:02 1.1
+++ ASTMulNode.java 2000/12/27 14:31:53 1.2
@@ -1,9 +1,75 @@
/* Generated By:JJTree: Do not edit this line. ASTMulNode.java */
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2000 The Apache Software Foundation. All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ * any, must include the following acknowlegement:
+ * "This product includes software developed by the
+ * Apache Software Foundation (http://www.apache.org/)."
+ * Alternately, this acknowlegement may appear in the software itself,
+ * if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
+ * Foundation" must not be used to endorse or promote products derived
+ * from this software without prior written permission. For written
+ * permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ * nor may "Apache" appear in their names without prior written
+ * permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation. For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+
+/**
+ * Handles integer multiplication
+ *
+ * Please look at the Parser.jjt file which is
+ * what controls the generation of this class.
+ *
+ * @author <a href="mailto:jvanzyl@periapt.com">Jason van Zyl</a>
+ * @author <a href="mailto:geirm@optonline.net">Geir Magnusson Jr.</a>
+ * @version $Id: ASTMulNode.java,v 1.2 2000/12/27 14:31:53 geirm Exp $
+*/
package org.apache.velocity.runtime.parser.node;
import org.apache.velocity.Context;
-import org.apache.velocity.runtime.parser.*;
+import org.apache.velocity.runtime.Runtime;
+import org.apache.velocity.runtime.parser.Parser;
public class ASTMulNode extends SimpleNode
{
@@ -23,10 +89,50 @@
return visitor.visit(this, data);
}
- public Object value(Context context)
+ /**
+ * computes the product of the two args. Returns null if either arg is null
+ * or if either arg is not an integer
+ */
+ public Object value( Context context )
{
- return new Integer(((Integer) jjtGetChild(0).value(context)).intValue() *
- ((Integer) jjtGetChild(1).value(context)).intValue());
- }
+ /*
+ * get the two args
+ */
+
+ Object left = jjtGetChild(0).value( context );
+ Object right = jjtGetChild(1).value( context );
+
+ /*
+ * if either is null, lets log and bail
+ */
+
+ if (left == null || right == null)
+ {
+ Runtime.error( ( left == null ? "Left" : "Right" ) + " side of multiplication operation has null value."
+ + " Operation not possible. "
+ + context.getCurrentTemplateName() + " [line " + getLine()
+ + ", column " + getColumn() + "]");
+ return null;
+ }
+
+ /*
+ * if not an Integer, not much we can do either
+ */
+
+ if ( !( left instanceof Integer ) || !( right instanceof Integer ))
+ {
+ Runtime.error( ( !( left instanceof Integer ) ? "Left" : "Right" )
+ + " side of multiplication operation is not a valid type. "
+ + "Currently only integers (1,2,3...) and Integer type is supported. "
+ + context.getCurrentTemplateName() + " [line " + getLine()
+ + ", column " + getColumn() + "]");
+
+ return null;
+ }
+ return new Integer( ( (Integer) left ).intValue() * ( (Integer) right ).intValue() );
+ }
}
+
+
+
1.2 +111 -3 jakarta-velocity/src/java/org/apache/velocity/runtime/parser/node/ASTSubtractNode.java
Index: ASTSubtractNode.java
===================================================================
RCS file: /home/cvs/jakarta-velocity/src/java/org/apache/velocity/runtime/parser/node/ASTSubtractNode.java,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- ASTSubtractNode.java 2000/10/20 19:14:02 1.1
+++ ASTSubtractNode.java 2000/12/27 14:31:54 1.2
@@ -1,9 +1,76 @@
/* Generated By:JJTree: Do not edit this line. ASTSubtractNode.java */
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2000 The Apache Software Foundation. All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ * any, must include the following acknowlegement:
+ * "This product includes software developed by the
+ * Apache Software Foundation (http://www.apache.org/)."
+ * Alternately, this acknowlegement may appear in the software itself,
+ * if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
+ * Foundation" must not be used to endorse or promote products derived
+ * from this software without prior written permission. For written
+ * permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ * nor may "Apache" appear in their names without prior written
+ * permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation. For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+
+/**
+ * Handles integer subtraction of nodes (in #set() )
+ *
+ * Please look at the Parser.jjt file which is
+ * what controls the generation of this class.
+ *
+ * @author <a href="mailto:jvanzyl@periapt.com">Jason van Zyl</a>
+ * @author <a href="mailto:geirm@optonline.net">Geir Magnusson Jr.</a>
+ * @version $Id: ASTSubtractNode.java,v 1.2 2000/12/27 14:31:54 geirm Exp $
+*/
+
package org.apache.velocity.runtime.parser.node;
import org.apache.velocity.Context;
-import org.apache.velocity.runtime.parser.*;
+import org.apache.velocity.runtime.Runtime;
+import org.apache.velocity.runtime.parser.Parser;
public class ASTSubtractNode extends SimpleNode
{
@@ -23,9 +90,50 @@
return visitor.visit(this, data);
}
+ /**
+ * computes the value of the subtraction. Currently
+ * limited to integers
+ * @return Integer(value) or null
+ */
public Object value(Context context)
{
- return new Integer(((Integer) jjtGetChild(0).value(context)).intValue() -
- ((Integer) jjtGetChild(1).value(context)).intValue());
+ /*
+ * get the two args
+ */
+
+ Object left = jjtGetChild(0).value( context );
+ Object right = jjtGetChild(1).value( context );
+
+ /*
+ * if either is null, lets log and bail
+ */
+
+ if (left == null || right == null)
+ {
+ Runtime.error( ( left == null ? "Left" : "Right" ) + " side of subtraction operation has null value."
+ + " Operation not possible. "
+ + context.getCurrentTemplateName() + " [line " + getLine()
+ + ", column " + getColumn() + "]");
+ return null;
+ }
+
+ /*
+ * if not an Integer, not much we can do either
+ */
+
+ if ( !( left instanceof Integer ) || !( right instanceof Integer ))
+ {
+ Runtime.error( ( !( left instanceof Integer ) ? "Left" : "Right" )
+ + " side of subtraction operation is not a valid type. "
+ + "Currently only integers (1,2,3...) and Integer type is supported. "
+ + context.getCurrentTemplateName() + " [line " + getLine()
+ + ", column " + getColumn() + "]");
+
+ return null;
+ }
+
+ return new Integer( ( (Integer) left ).intValue() - ( (Integer) right ).intValue() );
}
}
+
+