Commons Digester example source code file (SetNestedPropertiesRuleTestCase.java)

This example Commons Digester source code file (SetNestedPropertiesRuleTestCase.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 - Commons Digester tags/keywords

body, body, digester, io, ioexception, property, property, sax, saxexception, setnestedpropertiesrule, simpletestbean, simpletestbean, string, string, stringreader, test

The Commons Digester SetNestedPropertiesRuleTestCase.java source code

/* $Id: SetNestedPropertiesRuleTestCase.java 992060 2010-09-02 19:09:47Z simonetripodi $
 *
 * 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.digester;


import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.fail;

import java.io.IOException;
import java.io.Reader;
import java.io.StringReader;

import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.xml.sax.SAXException;


/**
 * <p> Test case for SetNestedPropertiesRule.
 * This contains tests for the main applications of the rule
 * and two more general tests of digester functionality used by this rule.
 */
public class SetNestedPropertiesRuleTestCase {


    // ----------------------------------------------------- Instance Variables

    /**
     * Simple test xml document used in the tests.
     */
    protected final static String TEST_XML =
        "<?xml version='1.0'?>" +
        "<root>ROOT BODY" +
        "<alpha>ALPHA BODY" +
        "<beta>BETA BODY" +
        "<gamma>GAMMA BODY" +
        "<delta>DELTA BODY" +
        "</root>";


    /**
     * The digester instance we will be processing.
     */
    protected Digester digester = null;


    // --------------------------------------------------- Overall Test Methods


    /**
     * Set up instance variables required by this test case.
     */
    @Before
    public void setUp() {

        digester = new Digester();

    }


    /**
     * Tear down instance variables required by this test case.
     */
    @After
    public void tearDown() {

        digester = null;

    }



    // ------------------------------------------------ Individual Test Methods


    /**
     * Test that you can successfully automatically set properties.
     */
    @Test
    public void testAutomaticallySetProperties()
        throws SAXException, IOException {

        // going to be setting properties on a SimpleTestBean
        digester.addObjectCreate("root",
                                 "org.apache.commons.digester.SimpleTestBean");

        // match all children of root with this rule
        digester.addRule("root", new SetNestedPropertiesRule());

        SimpleTestBean bean = (SimpleTestBean) digester.parse(xmlTestReader());

        // check properties are set correctly
        assertEquals(
                "Property alpha not set correctly",
                "ALPHA BODY",
                bean.getAlpha());

        assertEquals(
                "Property beta not set correctly",
                "BETA BODY",
                bean.getBeta());

        assertEquals(
                "Property gamma not set correctly",
                "GAMMA BODY",
                bean.getGamma());

        assertEquals(
                "Property delta not set correctly",
                "DELTA BODY",
                bean.getDeltaValue());
    }

    /**
     * Test that it is an error when a child element exists but no corresponding
     * java property exists.
     */
    @Test
    public void testMandatoryProperties()
        throws SAXException, IOException {

        String TEST_XML =
            "<?xml version='1.0'?>" +
            "<root>ROOT BODY" +
            "<badprop>ALPHA BODY" +
            "</root>";

        // going to be setting properties on a SimpleTestBean
        digester.addObjectCreate("root",
                                 "org.apache.commons.digester.SimpleTestBean");

        // match all children of root with this rule
        digester.addRule("root", new SetNestedPropertiesRule());

        try {
            SimpleTestBean bean = (SimpleTestBean) digester.parse(
                new StringReader(TEST_XML));

            // we should never get here...
            fail("No exception thrown by parse when unknown child element found.");
            assertNotNull(bean); // just to prevent compiler warning on unused var
        } catch(org.xml.sax.SAXParseException e) {
            String msg = e.getMessage();
            if (msg.indexOf("badprop") >= 0) {
                // ok, this is expected; there is no "setBadprop" method on the
                // SimpleTestBean class...
            } else {
                fail("Unexpected parse exception:" + e.getMessage());
            }
        }
    }

    /**
     * Test that you can customise the property mappings using the
     * constructor which takes arrays-of-strings.
     */
    @Test
    public void testCustomisedProperties1()
        throws SAXException, IOException {

        String TEST_XML =
            "<?xml version='1.0'?>" +
            "<root>ROOT BODY" +
            "<alpha>ALPHA BODY" +
            "<beta>BETA BODY" +
            "<gamma-alt>GAMMA BODY" +
            "<delta>DELTA BODY" +
            "</root>";

        // going to be setting properties on a SimpleTestBean
        digester.addObjectCreate("root",
                                 "org.apache.commons.digester.SimpleTestBean");

        // ignore the "alpha" element (target=null)
        // don't remap the "beta" element
        // map the gamma-alt element into the gamma property
        // ignore the delta element (no matching element in array)
        
        Rule rule = new SetNestedPropertiesRule(
            new String[]{"alpha", "gamma-alt", "delta"},
            new String[]{null, "gamma"});
            
        digester.addRule("root", rule);

        SimpleTestBean bean = (SimpleTestBean) digester.parse(
            new StringReader(TEST_XML));

        // check properties are set correctly
        assertEquals(
                "Property alpha was not ignored (it should be)",
                null,
                bean.getAlpha());

        assertEquals(
                "Property beta not set correctly",
                "BETA BODY",
                bean.getBeta());

        assertEquals(
                "Property gamma not set correctly",
                "GAMMA BODY",
                bean.getGamma());

        assertEquals(
                "Property delta was not ignored (it should be)",
                null,
                bean.getDeltaValue());
                
         // check no bad rules object is left
         assertEquals(
            "Digester rules object not reset.",
            RulesBase.class, digester.getRules().getClass());
    }

    /**
     * Test that you can ignore a single input xml element using the
     * constructor which takes a single remapping.
     */
    @Test
    public void testCustomisedProperties2a()
        throws SAXException, IOException {

        String TEST_XML =
            "<?xml version='1.0'?>" +
            "<root>ROOT BODY" +
            "<alpha>ALPHA BODY" +
            "<beta>BETA BODY" +
            "<gamma>GAMMA BODY" +
            "<delta>DELTA BODY" +
            "</root>";

        // going to be setting properties on a SimpleTestBean
        digester.addObjectCreate("root",
                                 "org.apache.commons.digester.SimpleTestBean");

        // ignore the "alpha" element (target=null)
        Rule rule = new SetNestedPropertiesRule("alpha", null);
        digester.addRule("root", rule);

        SimpleTestBean bean = (SimpleTestBean) digester.parse(
            new StringReader(TEST_XML));

        // check properties are set correctly
        assertEquals(
                "Property alpha was not ignored (it should be)",
                null,
                bean.getAlpha());

        assertEquals(
                "Property beta not set correctly",
                "BETA BODY",
                bean.getBeta());

        assertEquals(
                "Property gamma not set correctly",
                "GAMMA BODY",
                bean.getGamma());

        assertEquals(
                "Property delta not set correctly",
                "DELTA BODY",
                bean.getDeltaValue());

        // check no bad rules object is left
        assertEquals(
            "Digester rules object not reset.",
            RulesBase.class, digester.getRules().getClass());
    }

    /**
     * Test that you can customise the property mappings using the
     * constructor which takes a single remapping.
     */
    @Test
    public void testCustomisedProperties2b()
        throws SAXException, IOException {

        String TEST_XML =
            "<?xml version='1.0'?>" +
            "<root>ROOT BODY" +
            "<alpha-alt>ALPHA BODY" +
            "<beta>BETA BODY" +
            "<gamma>GAMMA BODY" +
            "<delta>DELTA BODY" +
            "</root>";

        // going to be setting properties on a SimpleTestBean
        digester.addObjectCreate("root",
                                 "org.apache.commons.digester.SimpleTestBean");

        // map the contents of the alpha-alt xml child into the
        // "alpha" java property.
        Rule rule = new SetNestedPropertiesRule("alpha-alt", "alpha");
        digester.addRule("root", rule);

        SimpleTestBean bean = (SimpleTestBean) digester.parse(
            new StringReader(TEST_XML));

        // check properties are set correctly
        assertEquals(
                "Property alpha not set correctly",
                "ALPHA BODY",
                bean.getAlpha());

        assertEquals(
                "Property beta not set correctly",
                "BETA BODY",
                bean.getBeta());

        assertEquals(
                "Property gamma not set correctly",
                "GAMMA BODY",
                bean.getGamma());

        assertEquals(
                "Property delta not set correctly",
                "DELTA BODY",
                bean.getDeltaValue());
                
         // check no bad rules object is left
         assertEquals(
            "Digester rules object not reset.",
            RulesBase.class, digester.getRules().getClass());
    }

    /**
     * Test that:
     * <ul>
     * <li> you can have rules matching the same pattern as the 
     *  SetNestedPropertiesRule, </li>
     * <li> you can have rules matching child elements of the rule, 
     * <li> the Rules object is reset nicely. 
     * </ul>
     */
    @Test
    public void testMultiRuleMatch()
        throws SAXException, IOException {

        String testXml =
            "<?xml version='1.0'?>" +
            "<root>" +
                "<testbean alpha='alpha-attr'>ROOT BODY" +
                    "<beta>BETA BODY" +
                    "<gamma>GAMMA " +
                    "<prop name='delta' value='delta-prop'/>" +
                    "BODY" +
                    "</gamma>" +
                "</testbean>" +
            "</root>";

        Reader reader = new StringReader(testXml);

        // going to be setting properties on a SimpleTestBean
        digester.addObjectCreate("root/testbean",
                                 "org.apache.commons.digester.SimpleTestBean");

        digester.addRule("root/testbean", new SetNestedPropertiesRule());
        digester.addSetProperties("root/testbean");
        digester.addSetProperty("root/testbean/gamma/prop", "name", "value");

        SimpleTestBean bean = (SimpleTestBean) digester.parse(reader);

        assertNotNull("No object created", bean);
        
        // check properties are set correctly
        assertEquals(
                "Property alpha not set correctly",
                "alpha-attr",
                bean.getAlpha());

        assertEquals(
                "Property beta not set correctly",
                "BETA BODY",
                bean.getBeta());

        assertEquals(
                "Property gamma not set correctly",
                "GAMMA BODY",
                bean.getGamma());

        assertEquals(
                "Property delta not set correctly",
                "delta-prop",
                bean.getDeltaValue());

         // check no bad rules object is left
         assertEquals(
            "Digester rules object not reset.",
            RulesBase.class, digester.getRules().getClass());
    }

    /**
     * Test that unknown child elements trigger an exception.
     */
    @Test
    public void testUnknownChildrenCausesException()
        throws SAXException, IOException {

        String testXml =
            "<?xml version='1.0'?>" +
            "<root>" +
                "<testbean>" +
                    "<beta>BETA BODY" +
                    "<foo>GAMMA" +
                "</testbean>" +
            "</root>";

        Reader reader = new StringReader(testXml);

        // going to be setting properties on a SimpleTestBean
        digester.addObjectCreate("root",
                                 "org.apache.commons.digester.SimpleTestBean");

        Rule rule = new SetNestedPropertiesRule();
        digester.addRule("root", rule);

        try {
            SimpleTestBean bean = (SimpleTestBean) digester.parse(reader);
            fail("Expected to generate an exception.");
            assertNotNull(bean); // just to prevent compiler warning on unused var
        } catch(SAXException e) {
            Exception nested = e.getException();
            if ((nested==null) || !(nested instanceof NoSuchMethodException)) {
                // nope, not the sort of exception we expected
                throw e;
            }
        }
    }

    /**
     * Test that unknown child elements are allowed if the appropriate
     * flag is set.
     */
    @Test
    public void testUnknownChildrenExceptionOverride()
        throws SAXException, IOException {

        String testXml =
            "<?xml version='1.0'?>" +
            "<root>" +
                "<testbean>" +
                    "<beta>BETA BODY" +
                    "<foo>GAMMA" +
                "</testbean>" +
            "</root>";

        Reader reader = new StringReader(testXml);

        // going to be setting properties on a SimpleTestBean
        digester.addObjectCreate("root",
                                 "org.apache.commons.digester.SimpleTestBean");

        SetNestedPropertiesRule rule = new SetNestedPropertiesRule();
        rule.setAllowUnknownChildElements(true);
        digester.addRule("root", rule);

        SimpleTestBean bean = (SimpleTestBean) digester.parse(reader);
        assertNotNull(bean);
    }

    /**
     * Test that the rule works in a sane manner when the associated pattern
     * is a wildcard such that the rule matches one of its own child elements.
     * <p>
     * See bugzilla entry 31393.
     */
    @Test
    public void testRecursiveNestedProperties()
        throws SAXException, IOException {

        String testXml =
            "<?xml version='1.0'?>" +
            "<testbean>" +
                "<beta>BETA BODY" +
                "<testbean>" +
                    "<beta>BETA BODY" +
                "</testbean>" +
            "</testbean>";

        Reader reader = new StringReader(testXml);

        // going to be setting properties on a SimpleTestBean
        digester.addObjectCreate("*/testbean",
                                 "org.apache.commons.digester.SimpleTestBean");

        SetNestedPropertiesRule rule = new SetNestedPropertiesRule();
        rule.setAllowUnknownChildElements(true);
        digester.addRule("*/testbean", rule);

        SimpleTestBean bean = (SimpleTestBean) digester.parse(reader);
        assertNotNull(bean);
    }


    /**
     * Get input stream from {@link #TEST_XML}.
     */
    private Reader xmlTestReader() {
        return new StringReader(TEST_XML);
    }

}