freemarker.core.Assignment Maven / Gradle / Ivy
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Google App Engine compliant variation of FreeMarker.
FreeMarker is a "template engine"; a generic tool to generate text output based on templates.
/*
* Copyright (c) 2003 The Visigoth Software Society. 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 acknowledgement:
* "This product includes software developed by the
* Visigoth Software Society (http://www.visigoths.org/)."
* Alternately, this acknowledgement may appear in the software itself,
* if and wherever such third-party acknowledgements normally appear.
*
* 4. Neither the name "FreeMarker", "Visigoth", nor any of the names of the
* project contributors may be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact [email protected].
*
* 5. Products derived from this software may not be called "FreeMarker" or "Visigoth"
* nor may "FreeMarker" or "Visigoth" appear in their names
* without prior written permission of the Visigoth Software Society.
*
* 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 VISIGOTH SOFTWARE SOCIETY 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 Visigoth Software Society. For more
* information on the Visigoth Software Society, please see
* http://www.visigoths.org/
*/
package freemarker.core;
import freemarker.template.*;
/**
* An instruction that assigns a literal or reference, to a single-identifier
* variable.
*/
final class Assignment extends TemplateElement {
private String variableName;
private Expression value, namespaceExp;
private int scope;
static final int NAMESPACE = 1;
static final int LOCAL = 2;
static final int GLOBAL = 3;
/**
* @param variableName the variable name to assign to.
* @param value the expression to assign.
* @param scope the scope of the assignment, one of NAMESPACE, LOCAL, or GLOBAL
*/
Assignment(String variableName,
Expression value,
int scope)
{
this.variableName = variableName;
this.value = value;
this.scope = scope;
}
void setNamespaceExp(Expression namespaceExp) {
this.namespaceExp = namespaceExp;
}
void accept(Environment env) throws TemplateException {
TemplateModel tm = value.getAsTemplateModel(env);
Environment.Namespace namespace = null;
if (namespaceExp != null) {
boolean oops = false;
try {
namespace = (Environment.Namespace) namespaceExp.getAsTemplateModel(env);
} catch (ClassCastException cce) {
oops = true;
}
if (oops || namespace==null) {
throw new InvalidReferenceException(getStartLocation() + "\nInvalid reference to namespace: " + namespaceExp, env);
}
}
if (tm == null) {
if (env.isClassicCompatible()) {
tm = TemplateScalarModel.EMPTY_STRING;
}
else {
String msg = "Error " + getStartLocation()
+"\n" + value + " is undefined."
+"\nIt cannot be assigned to " + variableName;
throw new InvalidReferenceException(msg, env);
}
}
if (scope == LOCAL) {
env.setLocalVariable(variableName, tm);
}
else {
if (namespace == null) {
if (scope == GLOBAL) {
namespace = env.getGlobalNamespace();
}
else if (scope == NAMESPACE) {
namespace = env.getCurrentNamespace();
}
}
namespace.put(variableName, tm);
}
}
public String getCanonicalForm() {
StringBuffer buf = new StringBuffer();
if (!(parent instanceof AssignmentInstruction)) {
if (scope == LOCAL) {
buf.append("<#local ");
}
else if (scope ==GLOBAL) {
buf.append("<#global ");
}
else {
buf.append("<#assign ");
}
}
buf.append (variableName);
buf.append('=');
buf.append(value.getCanonicalForm());
if (!(parent instanceof AssignmentInstruction)) {
if (namespaceExp != null) {
buf.append(" in ");
buf.append(namespaceExp.getCanonicalForm());
}
buf.append(">");
}
return buf.toString();
}
public String getDescription() {
String s ="";
if (!(parent instanceof AssignmentInstruction)) {
s = "assignment: ";
if (scope == LOCAL) {
s = "local " + s;
}
else if (scope == GLOBAL) {
s = "global " + s;
}
}
return s + variableName
+ "="
+ value;
}
}