Problem with jdom SaxBuilder

[Manuel Fernández Sánchez de la Blanca]

Hi everybody again.

I'm experiencing an error with jdom SaxBuilder when using PowerMock.

There are three attached files, two tests and a class with the static
method to mock. With Test.java (no mocking) everything's ok; and
Test2.java (with mocking) reproduces the error with the following error
stack trace:

org.jdom.JDOMException: Could not load default SAX parser:
org.apache.xerces.parsers.SAXParser: SAX2 driver class
org.apache.xerces.parsers.SAXParser does not implement XMLReader:
org.apache.xerces.parsers.SAXParser cannot be cast to org.xml.sax.XMLReader
at org.jdom.input.SAXBuilder.createParser(SAXBuilder.java:618)
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:460)
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:888)
at Test2.test(Test2.java:31)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.junit.internal.runners.TestMethod.invoke(TestMethod.java:59)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$2.runTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:217)
at org.junit.internal.runners.MethodRoadie$2.run(MethodRoadie.java:79)
at
org.junit.internal.runners.MethodRoadie.runBeforesThenTestThenAfters(MethodRoadie.java:87)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$2.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:207)
at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:77)
at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:42)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:202)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:156)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:130)
at
org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:27)
at
org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:37)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:128)
at
org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:112)
at
org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:44)
at
org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:45)
at
org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:460)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:673)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:386)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:196)
Caused by: java.lang.ClassCastException:
org.apache.xerces.parsers.SAXParser cannot be cast to org.xml.sax.XMLReader
at
org.xml.sax.helpers.XMLReaderFactory.loadClass(XMLReaderFactory.java:199)
at
org.xml.sax.helpers.XMLReaderFactory.createXMLReader(XMLReaderFactory.java:180)
at org.jdom.input.SAXBuilder.createParser(SAXBuilder.java:610)
... 28 more
Caused by: java.lang.ClassCastException:
org.apache.xerces.parsers.SAXParser cannot be cast to org.xml.sax.XMLReader
at
org.xml.sax.helpers.XMLReaderFactory.loadClass(XMLReaderFactory.java:199)
at
org.xml.sax.helpers.XMLReaderFactory.createXMLReader(XMLReaderFactory.java:180)
at org.jdom.input.SAXBuilder.createParser(SAXBuilder.java:610)
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:460)
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:888)
at Test2.test(Test2.java:31)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.junit.internal.runners.TestMethod.invoke(TestMethod.java:59)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$2.runTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:217)
at org.junit.internal.runners.MethodRoadie$2.run(MethodRoadie.java:79)
at
org.junit.internal.runners.MethodRoadie.runBeforesThenTestThenAfters(MethodRoadie.java:87)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$2.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:207)
at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:77)
at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:42)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:202)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:156)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:130)
at
org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:27)
at
org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:37)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:128)
at
org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:112)
at
org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:44)
at
org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:45)
at
org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:460)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:673)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:386)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:196)
Caused by: java.lang.ClassCastException:
org.apache.xerces.parsers.SAXParser cannot be cast to org.xml.sax.XMLReader
at
org.xml.sax.helpers.XMLReaderFactory.loadClass(XMLReaderFactory.java:187)
at
org.xml.sax.helpers.XMLReaderFactory.createXMLReader(XMLReaderFactory.java:180)
at org.jdom.input.SAXBuilder.createParser(SAXBuilder.java:610)
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:460)
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:888)
at Test2.test(Test2.java:31)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.junit.internal.runners.TestMethod.invoke(TestMethod.java:59)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$2.runTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:217)
at org.junit.internal.runners.MethodRoadie$2.run(MethodRoadie.java:79)
at
org.junit.internal.runners.MethodRoadie.runBeforesThenTestThenAfters(MethodRoadie.java:87)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$2.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:207)
at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:77)
at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:42)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:202)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:156)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:130)
at
org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:27)
at
org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:37)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:128)
at
org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:112)
at
org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:44)
at
org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:45)
at
org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:460)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:673)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:386)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:196)
Caused by: java.lang.ClassCastException:
org.apache.xerces.parsers.SAXParser cannot be cast to org.xml.sax.XMLReader
at
org.xml.sax.helpers.XMLReaderFactory.loadClass(XMLReaderFactory.java:199)
at
org.xml.sax.helpers.XMLReaderFactory.createXMLReader(XMLReaderFactory.java:180)
at org.jdom.input.SAXBuilder.createParser(SAXBuilder.java:610)
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:460)
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:888)
at Test2.test(Test2.java:31)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.junit.internal.runners.TestMethod.invoke(TestMethod.java:59)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$2.runTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:217)
at org.junit.internal.runners.MethodRoadie$2.run(MethodRoadie.java:79)
at
org.junit.internal.runners.MethodRoadie.runBeforesThenTestThenAfters(MethodRoadie.java:87)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$2.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:207)
at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:77)
at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:42)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:202)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:156)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:130)
at
org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:27)
at
org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:37)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:128)
at
org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:112)
at
org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:44)
at
org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:45)
at
org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:460)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:673)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:386)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:196)
Caused by: java.lang.ClassCastException:
org.apache.xerces.parsers.SAXParser cannot be cast to org.xml.sax.XMLReader
at
org.xml.sax.helpers.XMLReaderFactory.loadClass(XMLReaderFactory.java:187)
at
org.xml.sax.helpers.XMLReaderFactory.createXMLReader(XMLReaderFactory.java:180)
at org.jdom.input.SAXBuilder.createParser(SAXBuilder.java:610)
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:460)
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:888)
at Test2.test(Test2.java:31)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.junit.internal.runners.TestMethod.invoke(TestMethod.java:59)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$2.runTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:217)
at org.junit.internal.runners.MethodRoadie$2.run(MethodRoadie.java:79)
at
org.junit.internal.runners.MethodRoadie.runBeforesThenTestThenAfters(MethodRoadie.java:87)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$2.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:207)
at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:77)
at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:42)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:202)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:156)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:130)
at
org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:27)
at
org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:37)
at
org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:128)
at
org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:112)
at
org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:44)
at
org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:45)
at
org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:460)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:673)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:386)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:196)

[Johan Haleby]

Hi,

I don't have time to check this right now since I'm going on vacation tomorrow but I think that the problem is that the XML parsing framework are loading some classes from the system classloader by reflection. I've experienced this with dom4j. By the looks of it you could try suppressing the static initializer that calls the "org.xml.sax.helpers.XMLReaderFactory.createXMLReader(..)" method or perhaps try suppressing the method call to "org.xml.sax.helpers.XMLReaderFactory.loadClass(..)". You can use the @SuppressStaticInitializerFor annotation at the class-level to go with the first approach or use the suppressMethod(..) method from the PowerMock API to do the latter. Please have a look at the dom4j example in the code base. This would probably make a good mock policy as well.

Hope this helps,
/Johan

[Jan Kronquist]

In this scenario you are not actually using powermock for the jdom classes, but powermocks classloaders gets you in trouble anyway. This is a unfortunate sideeffect that we try hard to avoid, but sometimes this occur anyway.

A simple way to make powermock ignore certain classes is using the PowerMockIgnore annotation.  Like this

@PowerMockIgnore("org.jdom")

I have added an jdom example here:
http://powermock.googlecode.com/svn/trunk/examples/jdom/
http://powermock.googlecode.com/svn/trunk/examples/jdom/src/test/java/examples/jdom/StaticWithJdomTest.java


/Jan

[Manuel Fernandez Sanchez de la Blanca]

Hi.

Thanks for the reply.

Seriously, I'm very impressed about your work, the more I use Powermock the more I like it.

2009/1/19 Jan Kronquist <jan.kr...@gmail.com>

--

[Jan Kronquist]

Thanks!

/Jan