Spring Framework example source code file (ExpressionEvaluationUtilsTests.java)

This example Spring Framework source code file (ExpressionEvaluationUtilsTests.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Spring Framework tags/keywords

countingmockexpressionevaluator, countingmockexpressionevaluator, countingmockpagecontext, exception, exception, http, jsp, jspexception, jspexception, mockpagecontext, mockservletcontext, object, pagecontext, pagecontext, servlet, should, string

The Spring Framework ExpressionEvaluationUtilsTests.java source code

/*
 * Copyright 2002-2006 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.web.util;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.PageContext;
import javax.servlet.jsp.el.ELException;
import javax.servlet.jsp.el.Expression;
import javax.servlet.jsp.el.ExpressionEvaluator;
import javax.servlet.jsp.el.FunctionMapper;
import javax.servlet.jsp.el.VariableResolver;

import junit.framework.TestCase;

import org.springframework.mock.web.MockExpressionEvaluator;
import org.springframework.mock.web.MockPageContext;
import org.springframework.mock.web.MockServletContext;

/**
 * @author Aled Arendsen
 * @author Juergen Hoeller
 * @since 16.09.2003
 */
public class ExpressionEvaluationUtilsTests extends TestCase {

	public void testIsExpressionLanguage() {
		assertTrue(ExpressionEvaluationUtils.isExpressionLanguage("${bla}"));
		assertTrue(ExpressionEvaluationUtils.isExpressionLanguage("bla${bla}"));
		assertFalse(ExpressionEvaluationUtils.isExpressionLanguage("bla{bla"));
		assertFalse(ExpressionEvaluationUtils.isExpressionLanguage("bla$b{"));
	}

	public void testEvaluate() throws Exception {
		PageContext ctx = new MockPageContext();
		ctx.setAttribute("bla", "blie");

		assertEquals("blie", ExpressionEvaluationUtils.evaluate("test", "${bla}", String.class, ctx));
		assertEquals("test", ExpressionEvaluationUtils.evaluate("test", "test", String.class, ctx));

		try {
			ExpressionEvaluationUtils.evaluate("test", "test", Float.class, ctx);
			fail("Should have thrown JspException");
		}
		catch (JspException ex) {
			// expected
		}
	}

	public void testEvaluateWithConcatenation() throws Exception {
		PageContext ctx = new MockPageContext();
		ctx.setAttribute("bla", "blie");

		String expr = "text${bla}text${bla}text";
		Object o = ExpressionEvaluationUtils.evaluate("test", expr, String.class, ctx);
		assertEquals("textblietextblietext", o);

		expr = "${bla}text${bla}text";
		o = ExpressionEvaluationUtils.evaluate("test", expr, String.class, ctx);
		assertEquals("blietextblietext", o);

		expr = "${bla}text${bla}";
		o = ExpressionEvaluationUtils.evaluate("test", expr, String.class, ctx);
		assertEquals("blietextblie", o);

		expr = "${bla}text${bla}";
		o = ExpressionEvaluationUtils.evaluate("test", expr, Object.class, ctx);
		assertEquals("blietextblie", o);

		try {
			expr = "${bla}text${bla";
			ExpressionEvaluationUtils.evaluate("test", expr, Object.class, ctx);
			fail("Should have thrown JspException");
		}
		catch (JspException ex) {
			// expected
		}

		try {
			expr = "${bla}text${bla}";
			ExpressionEvaluationUtils.evaluate("test", expr, Float.class, ctx);
			fail("Should have thrown JspException");
		}
		catch (JspException ex) {
			// expected
		}
	}

	public void testEvaluateString() throws Exception {
		PageContext ctx = new MockPageContext();
		ctx.setAttribute("bla", "blie");

		assertEquals("blie", ExpressionEvaluationUtils.evaluateString("test", "${bla}", ctx));
		assertEquals("blie", ExpressionEvaluationUtils.evaluateString("test", "blie", ctx));
	}

	public void testEvaluateStringWithConcatenation() throws Exception {
		PageContext ctx = new MockPageContext();
		ctx.setAttribute("bla", "blie");

		String expr = "text${bla}text${bla}text";
		String s = ExpressionEvaluationUtils.evaluateString("test", expr, ctx);
		assertEquals("textblietextblietext", s);

		expr = "${bla}text${bla}text";
		s = ExpressionEvaluationUtils.evaluateString("test", expr, ctx);
		assertEquals("blietextblietext", s);

		expr = "${bla}text${bla}";
		s = ExpressionEvaluationUtils.evaluateString("test", expr, ctx);
		assertEquals("blietextblie", s);

		expr = "${bla}text${bla}";
		s = ExpressionEvaluationUtils.evaluateString("test", expr, ctx);
		assertEquals("blietextblie", s);

		try {
			expr = "${bla}text${bla";
			ExpressionEvaluationUtils.evaluateString("test", expr, ctx);
			fail("Should have thrown JspException");
		}
		catch (JspException ex) {
			// expected
		}

	}

	public void testEvaluateInteger() throws Exception {
		PageContext ctx = new MockPageContext();
		ctx.setAttribute("bla", new Integer(1));

		assertEquals(1, ExpressionEvaluationUtils.evaluateInteger("test", "${bla}", ctx));
		assertEquals(21, ExpressionEvaluationUtils.evaluateInteger("test", "21", ctx));
	}

	public void testEvaluateBoolean() throws Exception {
		PageContext ctx = new MockPageContext();
		ctx.setAttribute("bla", new Boolean(true));

		assertTrue(ExpressionEvaluationUtils.evaluateBoolean("test", "${bla}", ctx));
		assertTrue(ExpressionEvaluationUtils.evaluateBoolean("test", "true", ctx));
	}

	public void testEvaluateWithoutCaching() throws Exception {
		PageContext ctx = new CountingMockPageContext();
		CountingMockExpressionEvaluator eval = (CountingMockExpressionEvaluator) ctx.getExpressionEvaluator();
		ctx.setAttribute("bla", "blie");
		ctx.setAttribute("blo", "blue");

		assertEquals("blie", ExpressionEvaluationUtils.evaluate("test", "${bla}", String.class, ctx));
		assertEquals(1, eval.evaluateCount);

		assertEquals("blue", ExpressionEvaluationUtils.evaluate("test", "${blo}", String.class, ctx));
		assertEquals(2, eval.evaluateCount);

		assertEquals("blie", ExpressionEvaluationUtils.evaluate("test", "${bla}", String.class, ctx));
		assertEquals(3, eval.evaluateCount);

		assertEquals("blue", ExpressionEvaluationUtils.evaluate("test", "${blo}", String.class, ctx));
		assertEquals(4, eval.evaluateCount);
	}

	public void testEvaluateWithCaching() throws Exception {
		PageContext ctx = new CountingMockPageContext();
		CountingMockExpressionEvaluator eval = (CountingMockExpressionEvaluator) ctx.getExpressionEvaluator();
		ctx.setAttribute("bla", "blie");
		ctx.setAttribute("blo", "blue");

		MockServletContext sc = (MockServletContext) ctx.getServletContext();
		sc.addInitParameter(ExpressionEvaluationUtils.EXPRESSION_CACHE_CONTEXT_PARAM, "true");

		assertEquals("blie", ExpressionEvaluationUtils.evaluate("test", "${bla}", String.class, ctx));
		assertEquals(1, eval.parseExpressionCount);

		assertEquals("blue", ExpressionEvaluationUtils.evaluate("test", "${blo}", String.class, ctx));
		assertEquals(2, eval.parseExpressionCount);

		assertEquals("blie", ExpressionEvaluationUtils.evaluate("test", "${bla}", String.class, ctx));
		assertEquals(2, eval.parseExpressionCount);

		assertEquals("blue", ExpressionEvaluationUtils.evaluate("test", "${blo}", String.class, ctx));
		assertEquals(2, eval.parseExpressionCount);
	}

	public void testEvaluateWithConcatenationWithoutCaching() throws Exception {
		PageContext ctx = new CountingMockPageContext();
		CountingMockExpressionEvaluator eval = (CountingMockExpressionEvaluator) ctx.getExpressionEvaluator();
		ctx.setAttribute("bla", "blie");
		ctx.setAttribute("blo", "blue");

		String expr = "text${bla}text${blo}text";
		Object o = ExpressionEvaluationUtils.evaluate("test", expr, String.class, ctx);
		assertEquals("textblietextbluetext", o);
		assertEquals(2, eval.evaluateCount);

		expr = "${bla}text${blo}text";
		o = ExpressionEvaluationUtils.evaluate("test", expr, String.class, ctx);
		assertEquals("blietextbluetext", o);
		assertEquals(4, eval.evaluateCount);

		expr = "${bla}text${blo}";
		o = ExpressionEvaluationUtils.evaluate("test", expr, String.class, ctx);
		assertEquals("blietextblue", o);
		assertEquals(6, eval.evaluateCount);

		expr = "${bla}text${blo}";
		o = ExpressionEvaluationUtils.evaluate("test", expr, Object.class, ctx);
		assertEquals("blietextblue", o);
		assertEquals(8, eval.evaluateCount);
	}

	public void testEvaluateWithConcatenationWithCaching() throws Exception {
		PageContext ctx = new CountingMockPageContext();
		CountingMockExpressionEvaluator eval = (CountingMockExpressionEvaluator) ctx.getExpressionEvaluator();
		ctx.setAttribute("bla", "blie");
		ctx.setAttribute("blo", "blue");

		MockServletContext sc = (MockServletContext) ctx.getServletContext();
		sc.addInitParameter(ExpressionEvaluationUtils.EXPRESSION_CACHE_CONTEXT_PARAM, "true");

		String expr = "text${bla}text${blo}text";
		Object o = ExpressionEvaluationUtils.evaluate("test", expr, String.class, ctx);
		assertEquals("textblietextbluetext", o);
		assertEquals(2, eval.parseExpressionCount);

		expr = "${bla}text${blo}text";
		o = ExpressionEvaluationUtils.evaluate("test", expr, String.class, ctx);
		assertEquals("blietextbluetext", o);
		assertEquals(2, eval.parseExpressionCount);

		expr = "${bla}text${blo}";
		o = ExpressionEvaluationUtils.evaluate("test", expr, String.class, ctx);
		assertEquals("blietextblue", o);
		assertEquals(2, eval.parseExpressionCount);

		expr = "${bla}text${blo}";
		o = ExpressionEvaluationUtils.evaluate("test", expr, Object.class, ctx);
		assertEquals("blietextblue", o);
		assertEquals(2, eval.parseExpressionCount);
	}


	private static class CountingMockPageContext extends MockPageContext {

		private ExpressionEvaluator eval = new CountingMockExpressionEvaluator(this);

		public ExpressionEvaluator getExpressionEvaluator() {
			return eval;
		}
	}


	private static class CountingMockExpressionEvaluator extends MockExpressionEvaluator {

		public int parseExpressionCount = 0;

		public int evaluateCount = 0;

		public CountingMockExpressionEvaluator(PageContext pageContext) {
			super(pageContext);
		}

		public Expression parseExpression(String expression, Class expectedType, FunctionMapper functionMapper) throws ELException {
			this.parseExpressionCount++;
			return super.parseExpression(expression, expectedType, functionMapper);
		}

		public Object evaluate(String expression, Class expectedType, VariableResolver variableResolver, FunctionMapper functionMapper) throws ELException {
			this.evaluateCount++;
			return super.evaluate(expression, expectedType, variableResolver, functionMapper);
		}
	}

}