/*
* 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;
}
@Override
TemplateModel _eval(Environment env) throws TemplateException {
return _eval(env, this, left, left.eval(env), right, right.eval(env));
}
/**
* @param leftExp
* Used for error messages only; can be {@code null}
* @param rightExp
* Used for error messages only; can be {@code null}
*/
static TemplateModel _eval(Environment env,
TemplateObject parent,
Expression leftExp, TemplateModel leftModel,
Expression rightExp, TemplateModel rightModel)
throws TemplateModelException, TemplateException, NonStringException {
if (leftModel instanceof TemplateNumberModel && rightModel instanceof TemplateNumberModel) {
Number first = EvalUtil.modelToNumber((TemplateNumberModel) leftModel, leftExp);
Number second = EvalUtil.modelToNumber((TemplateNumberModel) rightModel, rightExp);
return _evalOnNumbers(env, parent, first, second);
} else if (leftModel instanceof TemplateSequenceModel && rightModel instanceof TemplateSequenceModel) {
return new ConcatenatedSequence((TemplateSequenceModel) leftModel, (TemplateSequenceModel) rightModel);
} else {
try {
String leftStr = EvalUtil.coerceModelToString(leftModel, leftExp, (String) null, true, env);
String rightStr = EvalUtil.coerceModelToString(rightModel, rightExp, (String) null, true, env);
if (leftStr == null) { // Signals that the model is markup output
if (leftModel instanceof TemplateMarkupOutputModel) {
TemplateMarkupOutputModel<?> leftMO = (TemplateMarkupOutputModel<?>) leftModel;
if (rightStr == null) { // Signals that the model is markup output
return concatMarkupOutputs(parent, leftMO, (TemplateMarkupOutputModel) rightModel);
}
return concatMarkupOutputs(parent, leftMO, leftMO.getOutputFormat().fromPlainTextByEscaping(rightStr));
} else {
leftStr = "null"; // For B.C. only; should be an error
// Falls through
}
}
if (rightStr == null) { // Signals that the model is markup output
TemplateMarkupOutputModel<?> rightMO = (TemplateMarkupOutputModel<?>) rightModel;
return concatMarkupOutputs(parent, rightMO.getOutputFormat().fromPlainTextByEscaping(leftStr), rightMO);
}
return new SimpleScalar(leftStr.concat(rightStr));
} catch (NonStringOrTemplateOutputException 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;
}
}
}
}
private static TemplateModel concatMarkupOutputs(TemplateObject parent, TemplateMarkupOutputModel leftMO,
TemplateMarkupOutputModel rightMO) throws TemplateModelException {
MarkupOutputFormat leftOF = leftMO.getOutputFormat();
MarkupOutputFormat rightOF = rightMO.getOutputFormat();
if (rightOF != leftOF) {
String rightPT;
String leftPT;
if ((rightPT = rightOF.getSourcePlainText(rightMO)) != null) {
return leftOF.concat(leftMO, leftOF.fromPlainTextByEscaping(rightPT));
} else if ((leftPT = leftOF.getSourcePlainText(leftMO)) != null) {
return rightOF.concat(rightOF.fromPlainTextByEscaping(leftPT), rightMO);
} else {
Object[] message = { "Concatenation left hand operand is in ", new _DelayedToString(leftOF),
" format, while the right hand operand is in ", new _DelayedToString(rightOF),
". Conversion to common format wasn't possible." };
if (parent instanceof Expression) {
throw new _TemplateModelException((Expression) parent, message);
} else {
throw new _TemplateModelException(message);
}
}
} else {
return leftOF.concat(leftMO, rightMO);
}
}
static TemplateModel _evalOnNumbers(Environment env, TemplateObject parent, Number first, Number second)
throws TemplateException {
ArithmeticEngine ae = EvalUtil.getArithmeticEngine(env, parent);
return new SimpleNumber(ae.add(first, second));
}
@Override
boolean isLiteral() {
return constantValue != null || (left.isLiteral() && right.isLiteral());
}
@Override
protected Expression deepCloneWithIdentifierReplaced_inner(
String replacedIdentifier, Expression replacement, ReplacemenetState replacementState) {
return new AddConcatExpression(
left.deepCloneWithIdentifierReplaced(replacedIdentifier, replacement, replacementState),
right.deepCloneWithIdentifierReplaced(replacedIdentifier, replacement, replacementState));
}
@Override
public String getCanonicalForm() {
return left.getCanonicalForm() + " + " + right.getCanonicalForm();
}
@Override
String getNodeTypeSymbol() {
return "+";
}
@Override
int getParameterCount() {
return 2;
}
@Override
Object getParameterValue(int idx) {
return idx == 0 ? left : right;
}
@Override
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);
}
}
}
}