/*
* Copyright 2014 Attila Szegedi, Daniel Dekany, Jonathan Revusky
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package freemarker.core;
import java.util.HashSet;
import java.util.Set;
import freemarker.template.SimpleNumber;
import freemarker.template.SimpleScalar;
import freemarker.template.SimpleSequence;
import freemarker.template.TemplateCollectionModel;
import freemarker.template.TemplateException;
import freemarker.template.TemplateHashModel;
import freemarker.template.TemplateHashModelEx;
import freemarker.template.TemplateModel;
import freemarker.template.TemplateModelException;
import freemarker.template.TemplateModelIterator;
import freemarker.template.TemplateNumberModel;
import freemarker.template.TemplateScalarModel;
import freemarker.template.TemplateSequenceModel;
/**
* An operator for the + operator. Note that this is treated
* separately from the other 4 arithmetic operators,
* since + is overloaded to mean string concatenation.
*/
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 _eval(Environment env)
throws TemplateException
{
TemplateModel leftModel = left.eval(env);
TemplateModel rightModel = right.eval(env);
if (leftModel instanceof TemplateNumberModel && rightModel instanceof TemplateNumberModel)
{
Number first = EvalUtil.modelToNumber((TemplateNumberModel) leftModel, left);
Number second = EvalUtil.modelToNumber((TemplateNumberModel) rightModel, right);
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 = Expression.coerceModelToString(leftModel, left, env);
if(s1 == null) s1 = "null";
String s2 = Expression.coerceModelToString(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());
}
protected Expression deepCloneWithIdentifierReplaced_inner(
String replacedIdentifier, Expression replacement, ReplacemenetState replacementState) {
return new AddConcatExpression(
left.deepCloneWithIdentifierReplaced(replacedIdentifier, replacement, replacementState),
right.deepCloneWithIdentifierReplaced(replacedIdentifier, replacement, replacementState));
}
public String getCanonicalForm() {
return left.getCanonicalForm() + " + " + right.getCanonicalForm();
}
String getNodeTypeSymbol() {
return "+";
}
int getParameterCount() {
return 2;
}
Object getParameterValue(int idx) {
return idx == 0 ? left : right;
}
ParameterRole getParameterRole(int idx) {
return ParameterRole.forBinaryOperatorOperand(idx);
}
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);
}
}
}
}