/*
* Copyright 2002-2009 the original author or authors.
*
* 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 org.springframework.expression.common;
import org.springframework.core.convert.TypeDescriptor;
import org.springframework.expression.EvaluationContext;
import org.springframework.expression.EvaluationException;
import org.springframework.expression.Expression;
/**
* Represents a template expression broken into pieces. Each piece will be an Expression but pure text parts to the
* template will be represented as LiteralExpression objects. An example of a template expression might be:
*
* <pre class="code">
* "Hello ${getName()}"</pre>
*
* which will be represented as a CompositeStringExpression of two parts. The first part being a
* LiteralExpression representing 'Hello ' and the second part being a real expression that will
* call <code>getName()</code> when invoked.
*
* @author Andy Clement
* @author Juergen Hoeller
* @since 3.0
*/
public class CompositeStringExpression implements Expression {
private final String expressionString;
/** The array of expressions that make up the composite expression */
private final Expression[] expressions;
public CompositeStringExpression(String expressionString, Expression[] expressions) {
this.expressionString = expressionString;
this.expressions = expressions;
}
public final String getExpressionString() {
return this.expressionString;
}
public String getValue() throws EvaluationException {
StringBuilder sb = new StringBuilder();
for (Expression expression : this.expressions) {
String value = expression.getValue(String.class);
if (value != null) {
sb.append(value);
}
}
return sb.toString();
}
public String getValue(Object rootObject) throws EvaluationException {
StringBuilder sb = new StringBuilder();
for (Expression expression : this.expressions) {
String value = expression.getValue(rootObject, String.class);
if (value != null) {
sb.append(value);
}
}
return sb.toString();
}
public String getValue(EvaluationContext context) throws EvaluationException {
StringBuilder sb = new StringBuilder();
for (Expression expression : this.expressions) {
String value = expression.getValue(context, String.class);
if (value != null) {
sb.append(value);
}
}
return sb.toString();
}
public String getValue(EvaluationContext context, Object rootObject) throws EvaluationException {
StringBuilder sb = new StringBuilder();
for (Expression expression : this.expressions) {
String value = expression.getValue(context, rootObject, String.class);
if (value != null) {
sb.append(value);
}
}
return sb.toString();
}
public Class getValueType(EvaluationContext context) {
return String.class;
}
public Class getValueType() {
return String.class;
}
public TypeDescriptor getValueTypeDescriptor(EvaluationContext context) {
return TypeDescriptor.valueOf(String.class);
}
public TypeDescriptor getValueTypeDescriptor() {
return TypeDescriptor.valueOf(String.class);
}
public void setValue(EvaluationContext context, Object value) throws EvaluationException {
throw new EvaluationException(this.expressionString, "Cannot call setValue on a composite expression");
}
public <T> T getValue(EvaluationContext context, Class<T> expectedResultType) throws EvaluationException {
Object value = getValue(context);
return ExpressionUtils.convert(context, value, expectedResultType);
}
public <T> T getValue(Class<T> expectedResultType) throws EvaluationException {
Object value = getValue();
return ExpressionUtils.convert(null, value, expectedResultType);
}
public boolean isWritable(EvaluationContext context) {
return false;
}
public Expression[] getExpressions() {
return expressions;
}
public <T> T getValue(Object rootObject, Class<T> desiredResultType) throws EvaluationException {
Object value = getValue(rootObject);
return ExpressionUtils.convert(null, value, desiredResultType);
}
public <T> T getValue(EvaluationContext context, Object rootObject, Class<T> desiredResultType)
throws EvaluationException {
Object value = getValue(context,rootObject);
return ExpressionUtils.convert(context, value, desiredResultType);
}
public Class getValueType(Object rootObject) throws EvaluationException {
return String.class;
}
public Class getValueType(EvaluationContext context, Object rootObject) throws EvaluationException {
return String.class;
}
public TypeDescriptor getValueTypeDescriptor(Object rootObject) throws EvaluationException {
return TypeDescriptor.valueOf(String.class);
}
public TypeDescriptor getValueTypeDescriptor(EvaluationContext context, Object rootObject) throws EvaluationException {
return TypeDescriptor.valueOf(String.class);
}
public boolean isWritable(EvaluationContext context, Object rootObject) throws EvaluationException {
return false;
}
public void setValue(EvaluationContext context, Object rootObject, Object value) throws EvaluationException {
throw new EvaluationException(this.expressionString, "Cannot call setValue on a composite expression");
}
public boolean isWritable(Object rootObject) throws EvaluationException {
return false;
}
public void setValue(Object rootObject, Object value) throws EvaluationException {
throw new EvaluationException(this.expressionString, "Cannot call setValue on a composite expression");
}
}
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