freemarker.core.AddConcatExpression 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
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* 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.*;
import java.util.*;
/**
* An operator for the + operator. Note that this is treated
* separately from the other 4 arithmetic operators,
* since + is overloaded to mean string concatenation.
* @author Jonathan Revusky
*/
final class AddConcatExpression extends Expression {
private final Expression left;
private final Expression right;
AddConcatExpression(Expression left, Expression right) {
this.left = left;
this.right = right;
}
TemplateModel _getAsTemplateModel(Environment env)
throws TemplateException
{
TemplateModel leftModel = left.getAsTemplateModel(env);
TemplateModel rightModel = right.getAsTemplateModel(env);
if (leftModel instanceof TemplateNumberModel && rightModel instanceof TemplateNumberModel)
{
Number first = EvaluationUtil.getNumber((TemplateNumberModel) leftModel, left, env);
Number second = EvaluationUtil.getNumber((TemplateNumberModel) rightModel, right, env);
ArithmeticEngine ae =
env != null
? env.getArithmeticEngine()
: getTemplate().getArithmeticEngine();
return new SimpleNumber(ae.add(first, second));
}
else if(leftModel instanceof TemplateSequenceModel && rightModel instanceof TemplateSequenceModel)
{
return new ConcatenatedSequence((TemplateSequenceModel)leftModel, (TemplateSequenceModel)rightModel);
}
else
{
try {
String s1 = getStringValue(leftModel, left, env);
if(s1 == null) s1 = "null";
String s2 = getStringValue(rightModel, right, env);
if(s2 == null) s2 = "null";
return new SimpleScalar(s1.concat(s2));
} catch (NonStringException e) {
if (leftModel instanceof TemplateHashModel && rightModel instanceof TemplateHashModel) {
if (leftModel instanceof TemplateHashModelEx && rightModel instanceof TemplateHashModelEx) {
TemplateHashModelEx leftModelEx = (TemplateHashModelEx)leftModel;
TemplateHashModelEx rightModelEx = (TemplateHashModelEx)rightModel;
if (leftModelEx.size() == 0) {
return rightModelEx;
} else if (rightModelEx.size() == 0) {
return leftModelEx;
} else {
return new ConcatenatedHashEx(leftModelEx, rightModelEx);
}
} else {
return new ConcatenatedHash((TemplateHashModel)leftModel,
(TemplateHashModel)rightModel);
}
} else {
throw e;
}
}
}
}
boolean isLiteral() {
return constantValue != null || (left.isLiteral() && right.isLiteral());
}
Expression _deepClone(String name, Expression subst) {
return new AddConcatExpression(left.deepClone(name, subst), right.deepClone(name, subst));
}
public String getCanonicalForm() {
return left.getCanonicalForm() + " + " + right.getCanonicalForm();
}
private static final class ConcatenatedSequence
implements
TemplateSequenceModel
{
private final TemplateSequenceModel left;
private final TemplateSequenceModel right;
ConcatenatedSequence(TemplateSequenceModel left, TemplateSequenceModel right)
{
this.left = left;
this.right = right;
}
public int size()
throws
TemplateModelException
{
return left.size() + right.size();
}
public TemplateModel get(int i)
throws
TemplateModelException
{
int ls = left.size();
return i < ls ? left.get(i) : right.get(i - ls);
}
}
private static class ConcatenatedHash
implements TemplateHashModel
{
protected final TemplateHashModel left;
protected final TemplateHashModel right;
ConcatenatedHash(TemplateHashModel left, TemplateHashModel right)
{
this.left = left;
this.right = right;
}
public TemplateModel get(String key)
throws TemplateModelException
{
TemplateModel model = right.get(key);
return (model != null) ? model : left.get(key);
}
public boolean isEmpty()
throws TemplateModelException
{
return left.isEmpty() && right.isEmpty();
}
}
private static final class ConcatenatedHashEx
extends ConcatenatedHash
implements TemplateHashModelEx
{
private CollectionAndSequence keys;
private CollectionAndSequence values;
private int size;
ConcatenatedHashEx(TemplateHashModelEx left, TemplateHashModelEx right)
{
super(left, right);
}
public int size() throws TemplateModelException
{
initKeys();
return size;
}
public TemplateCollectionModel keys()
throws TemplateModelException
{
initKeys();
return keys;
}
public TemplateCollectionModel values()
throws TemplateModelException
{
initValues();
return values;
}
private void initKeys()
throws TemplateModelException
{
if (keys == null) {
HashSet keySet = new HashSet();
SimpleSequence keySeq = new SimpleSequence(32);
addKeys(keySet, keySeq, (TemplateHashModelEx)this.left);
addKeys(keySet, keySeq, (TemplateHashModelEx)this.right);
size = keySet.size();
keys = new CollectionAndSequence(keySeq);
}
}
private static void addKeys(Set set, SimpleSequence keySeq, TemplateHashModelEx hash)
throws TemplateModelException
{
TemplateModelIterator it = hash.keys().iterator();
while (it.hasNext()) {
TemplateScalarModel tsm = (TemplateScalarModel)it.next();
if (set.add(tsm.getAsString())) {
// The first occurence of the key decides the index;
// this is consisten with stuff like java.util.LinkedHashSet.
keySeq.add(tsm);
}
}
}
private void initValues()
throws TemplateModelException
{
if (values == null) {
SimpleSequence seq = new SimpleSequence(size());
// Note: size() invokes initKeys() if needed.
int ln = keys.size();
for (int i = 0; i < ln; i++) {
seq.add(get(((TemplateScalarModel)keys.get(i)).getAsString()));
}
values = new CollectionAndSequence(seq);
}
}
}
}