/*
* 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 freemarker.template.SimpleNumber;
import freemarker.template.TemplateException;
import freemarker.template.TemplateModel;
import freemarker.template.TemplateNumberModel;
final class UnaryPlusMinusExpression extends Expression {
private final int TYPE_MINUS = 0;
private final int TYPE_PLUS = 1;
private final Expression target;
private final boolean isMinus;
private static final Integer MINUS_ONE = new Integer(-1);
UnaryPlusMinusExpression(Expression target, boolean isMinus) {
this.target = target;
this.isMinus = isMinus;
}
TemplateModel _eval(Environment env) throws TemplateException {
TemplateNumberModel targetModel = null;
TemplateModel tm = target.eval(env);
try {
targetModel = (TemplateNumberModel) tm;
} catch (ClassCastException cce) {
throw new NonNumericalException(target, tm, env);
}
if (!isMinus) {
return targetModel;
}
target.assertNonNull(targetModel, env);
Number n = targetModel.getAsNumber();
n = ArithmeticEngine.CONSERVATIVE_ENGINE.multiply(MINUS_ONE, n);
return new SimpleNumber(n);
}
public String getCanonicalForm() {
String op = isMinus ? "-" : "+";
return op + target.getCanonicalForm();
}
String getNodeTypeSymbol() {
return isMinus ? "-..." : "+...";
}
boolean isLiteral() {
return target.isLiteral();
}
protected Expression deepCloneWithIdentifierReplaced_inner(
String replacedIdentifier, Expression replacement, ReplacemenetState replacementState) {
return new UnaryPlusMinusExpression(
target.deepCloneWithIdentifierReplaced(replacedIdentifier, replacement, replacementState),
isMinus);
}
boolean isIgnorable() {
return true;
}
int getParameterCount() {
return 2;
}
Object getParameterValue(int idx) {
switch (idx) {
case 0: return target;
case 1: return new Integer(isMinus ? TYPE_MINUS : TYPE_PLUS);
default: throw new IndexOutOfBoundsException();
}
}
ParameterRole getParameterRole(int idx) {
switch (idx) {
case 0: return ParameterRole.RIGHT_HAND_OPERAND;
case 1: return ParameterRole.AST_NODE_SUBTYPE;
default: throw new IndexOutOfBoundsException();
}
}
}