问题
I'm trying to get XmlPullParser working as it makes a lot more sense than the alternatives. However I'm falling at the first hurdle as the XmlPullParserFactory.newInstance() function is returning a null factory (seen by the debugger). Thus an exception is raised as soon as factory.newPullParser() is called.
import java.io.IOException;
import java.io.InputStream;
import java.io.StringReader;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import org.xmlpull.v1.XmlPullParserFactory;
public class XMLParser
{
public static void getXML(InputStream in)
throws XmlPullParserException, IOException {
try {
XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
XmlPullParser xpp = factory.newPullParser();
xpp.setInput(new StringReader("<foo>Hello World!</foo>"));
int eventType = xpp.getEventType();
while (eventType != XmlPullParser.END_DOCUMENT) {
if (eventType == XmlPullParser.START_DOCUMENT) {
System.out.println("Start document");
} else if (eventType == XmlPullParser.START_TAG) {
System.out.println("Start tag " + xpp.getName());
} else if (eventType == XmlPullParser.END_TAG) {
System.out.println("End tag " + xpp.getName());
} else if (eventType == XmlPullParser.TEXT) {
System.out.println("Text " + xpp.getText());
}
eventType = xpp.next();
}
System.out.println("End document");
} catch (Exception e) {
}
}
}
I'm calling this method from a Unit Test. I'm really stumped as to what the issue could be as I've not found any posts that have had issues like this.
Trace report: Full thread dump
"main@1" prio=5 tid=0x1 nid=NA runnable
java.lang.Thread.State: RUNNABLE
at com.company.app.XMLParser.getXmln(XMLParser.java:40)
at com.company.app.XMLParserTest.setUp(XMLParserTest.java:36)
at sun.reflect.NativeMethodAccessorImpl.invoke0(NativeMethodAccessorImpl.java:-1)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:24)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:78)
at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:212)
at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:68)
"Finalizer@836" daemon prio=8 tid=0x3 nid=NA waiting
java.lang.Thread.State: WAITING
at java.lang.Object.wait(Object.java:-1)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:143)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:164)
at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:209)
"Reference Handler@837" daemon prio=10 tid=0x2 nid=NA waiting
java.lang.Thread.State: WAITING
at java.lang.Object.wait(Object.java:-1)
at java.lang.Object.wait(Object.java:502)
at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:157)
"Attach Listener@834" daemon prio=5 tid=0x5 nid=NA runnable
java.lang.Thread.State: RUNNABLE
"Signal Dispatcher@835" daemon prio=9 tid=0x4 nid=NA runnable
java.lang.Thread.State: RUNNABLE
回答1:
You cannot unit test components of Android. The JAR file used for compilation only contains method stubs throwing exceptions. Consider a simple test case for your issue
public class UnitTest {
@Test
public void instanceNotNull() throws Exception {
assertNotNull(XmlPullParserFactory.newInstance());
}
}
Running it without any configuration defined, you'll get a
java.lang.RuntimeException: Method newInstance in org.xmlpull.v1.XmlPullParserFactory not mocked. See http://g.co/androidstudio/not-mocked for details.
at org.xmlpull.v1.XmlPullParserFactory.newInstance(XmlPullParserFactory.java)
at ...
When adding
testOptions {
unitTests.returnDefaultValues = true
}
to your gradle android configuration, you'll find the test just fail on the assertion.
If you want to test with the android library, you need to do it on a device with an instrumented test. So put your test case in the androidTest source set, add
dependencies {
testCompile 'junit:junit:4.12'
androidTestCompile 'com.android.support.test:runner:0.4'
}
to the gradle file of your module and run it on a device.
For more information see Testing Concepts and Testing Support Library.
回答2:
Just add this line to your wish list
(new Thread() {
@Override
public void run() {
try {
XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
XmlPullParser xpp = factory.newPullParser();
xpp.setInput(new StringReader("<foo>Hello World!</foo>"));
int eventType = xpp.getEventType();
while (eventType != XmlPullParser.END_DOCUMENT) {
if (eventType == XmlPullParser.START_DOCUMENT) {
System.out.println("Start document");
} else if (eventType == XmlPullParser.START_TAG) {
System.out.println("Start tag " + xpp.getName());
} else if (eventType == XmlPullParser.END_TAG) {
System.out.println("End tag " + xpp.getName());
} else if (eventType == XmlPullParser.TEXT) {
System.out.println("Text " + xpp.getText());
}
eventType = xpp.next();
}
System.out.println("End document");
} catch (Exception e) {
}
}
}
).start();
来源：https://stackoverflow.com/questions/35626721/android-xmlpullparserfactory-newinstance-creating-a-null-factory