/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.commons.jexl2.junit;
import java.math.BigDecimal;
import java.util.HashMap;
import java.util.Map;
import junit.framework.Assert;
import org.apache.commons.jexl2.Expression;
import org.apache.commons.jexl2.JexlArithmetic;
import org.apache.commons.jexl2.JexlContext;
import org.apache.commons.jexl2.MapContext;
import org.apache.commons.jexl2.JexlEngine;
import org.apache.commons.jexl2.JexlException;
import org.apache.commons.jexl2.JexlThreadedArithmetic;
/**
* A utility class for performing JUnit based assertions using Jexl
* expressions. This class can make it easier to do unit tests using
* Jexl navigation expressions.
*
* @since 1.0
*/
public class Asserter extends Assert {
/** variables used during asserts. */
private final Map<String, Object> variables = new HashMap<String, Object>();
/** context to use during asserts. */
private final JexlContext context = new MapContext(variables);
/** Jexl engine to use during Asserts. */
private final JexlEngine engine;
/**
*
* Create an asserter.
* @param jexl the JEXL engine to use
*/
public Asserter(JexlEngine jexl) {
engine = jexl;
}
/**
* Retrieves the underlying JEXL engine.
* @return the JEXL engine
*/
public JexlEngine getEngine() {
return engine;
}
/**
* Retrieves the underlying JEXL context.
* @return the JEXL context
*/
public JexlContext getContext() {
return context;
}
/**
* Performs an assertion that the value of the given Jexl expression
* evaluates to the given expected value.
*
* @param expression is the Jexl expression to evaluate
* @param expected is the expected value of the expression
* @throws Exception if the expression could not be evaluationed or an assertion
* fails
*/
public void assertExpression(String expression, Object expected) throws Exception {
Expression exp = engine.createExpression(expression);
Object value = exp.evaluate(context);
if (expected instanceof BigDecimal) {
JexlArithmetic jexla = engine.getArithmetic();
assertTrue("expression: " + expression, ((BigDecimal) expected).compareTo(jexla.toBigDecimal(value)) == 0);
} else {
assertEquals("expression: " + expression, expected, value);
}
}
/**
* Performs an assertion that the expression fails throwing an exception.
* If matchException is not null, the exception message is expected to match it as a regexp.
* The engine is temporarily switched to strict * verbose to maximize error detection abilities.
* @param expression the expression that should fail
* @param matchException the exception message pattern
* @throws Exception if the expression did not fail or the exception did not match the expected pattern
*/
public void failExpression(String expression, String matchException) throws Exception {
boolean[] flags = {engine.isLenient(), engine.isSilent()};
try {
if (engine.getArithmetic() instanceof JexlThreadedArithmetic) {
engine.setLenient(false);
}
engine.setSilent(false);
Expression exp = engine.createExpression(expression);
exp.evaluate(context);
fail("expression: " + expression);
} catch (JexlException xjexl) {
if (matchException != null && !xjexl.getMessage().matches(matchException)) {
fail("expression: " + expression + ", expected: " + matchException + ", got " + xjexl.getMessage());
}
} finally {
if (engine.getArithmetic() instanceof JexlThreadedArithmetic) {
engine.setLenient(flags[0]);
}
engine.setSilent(flags[1]);
}
}
/**
* Puts a variable of a certain name in the context so that it can be used from
* assertion expressions.
*
* @param name variable name
* @param value variable value
*/
public void setVariable(String name, Object value) {
variables.put(name, value);
}
/**
* Removes a variable of a certain name from the context.
* @param name variable name
* @return variable value
*/
public Object removeVariable(String name) {
return variables.remove(name);
}
}