Fleshed it out a bit more with comment. It looks like the
ProviderFactory.Comparator will choose whichever class in the parent/child
lineage which implements ExceptionMapper and base its ordering on that.
This means that a parent class cannot implement ExceptionMapper unless the
child ALSO implments ExceptionMapper.
package foo.test;
import static org.junit.Assert.*;
import javax.ws.rs.core.Response;
import javax.ws.rs.ext.ExceptionMapper;
import javax.ws.rs.ext.Provider;
import org.apache.cxf.jaxrs.provider.ProviderFactory;
import org.apache.cxf.message.MessageImpl;
public class ExceptionMapperTest {
@org.junit.Before
public void setup() {
ProviderFactory.getInstance().clearProviders();
}
@org.junit.Test
public void testBadCustomExceptionMappersHierarchyWithGenerics() throws
Exception {
ProviderFactory pf = ProviderFactory.getInstance();
BadExceptionMapperA badExceptionMapperA = new BadExceptionMapperA();
pf.registerUserProvider(badExceptionMapperA);
BadExceptionMapperB badExceptionMapperB = new BadExceptionMapperB();
pf.registerUserProvider(badExceptionMapperB);
Object mapperResponse1 =
pf.createExceptionMapper(RuntimeExceptionA.class, new MessageImpl());
assertSame(badExceptionMapperA, mapperResponse1);
Object mapperResponse2 =
pf.createExceptionMapper(RuntimeExceptionB.class, new MessageImpl());
assertSame(badExceptionMapperB, mapperResponse2);
Object mapperResponse3 =
pf.createExceptionMapper(RuntimeExceptionAA.class, new MessageImpl());
assertSame(badExceptionMapperA, mapperResponse3);
Object mapperResponse4 =
pf.createExceptionMapper(RuntimeExceptionBB.class, new MessageImpl());
assertSame(badExceptionMapperB, mapperResponse4);
}
/**
* To fix the problem the mapper must NOT extend from a class that
implements the ExceptionMapper interface. The parent class should be
* a normal java class and the mapper should implement the ExceptionMapper
interface DIRECTLY!
*
* @throws Exception
*/
@org.junit.Test
public void testFixedCustomExceptionMappersHierarchyWithGenerics() throws
Exception {
ProviderFactory pf = ProviderFactory.getInstance();
FixedExceptionMapperA exceptionMapperA = new FixedExceptionMapperA();
pf.registerUserProvider(exceptionMapperA);
FixedExceptionMapperB exceptionMapperB = new FixedExceptionMapperB();
pf.registerUserProvider(exceptionMapperB);
Object mapperResponse1 =
pf.createExceptionMapper(RuntimeExceptionA.class, new MessageImpl());
assertSame(exceptionMapperA, mapperResponse1);
Object mapperResponse2 =
pf.createExceptionMapper(RuntimeExceptionB.class, new MessageImpl());
assertSame(exceptionMapperB, mapperResponse2);
Object mapperResponse3 =
pf.createExceptionMapper(RuntimeExceptionAA.class, new MessageImpl());
assertSame(exceptionMapperA, mapperResponse3);
Object mapperResponse4 =
pf.createExceptionMapper(RuntimeExceptionBB.class, new MessageImpl());
assertSame(exceptionMapperB, mapperResponse4);
}
@org.junit.Test
public void testGoodExceptionMappersHierarchyWithGenerics() throws
Exception {
ProviderFactory pf = ProviderFactory.getInstance();
GoodRuntimeExceptionAMapper runtimeExceptionAMapper = new
GoodRuntimeExceptionAMapper();
pf.registerUserProvider(runtimeExceptionAMapper);
GoodRuntimeExceptionBMapper runtimeExceptionBMapper = new
GoodRuntimeExceptionBMapper();
pf.registerUserProvider(runtimeExceptionBMapper);
Object mapperResponse1 =
pf.createExceptionMapper(RuntimeExceptionA.class, new MessageImpl());
assertSame(runtimeExceptionAMapper, mapperResponse1);
Object mapperResponse2 =
pf.createExceptionMapper(RuntimeExceptionB.class, new MessageImpl());
assertSame(runtimeExceptionBMapper, mapperResponse2);
Object mapperResponse3 =
pf.createExceptionMapper(RuntimeExceptionAA.class, new MessageImpl());
assertSame(runtimeExceptionAMapper, mapperResponse3);
Object mapperResponse4 =
pf.createExceptionMapper(RuntimeExceptionBB.class, new MessageImpl());
assertSame(runtimeExceptionBMapper, mapperResponse4);
}
private class RuntimeExceptionA extends RuntimeException {
private static final long serialVersionUID = 1L;
}
private class RuntimeExceptionAA extends RuntimeExceptionA {
private static final long serialVersionUID = 1L;
}
private class RuntimeExceptionB extends RuntimeException {
private static final long serialVersionUID = 1L;
}
private class RuntimeExceptionBB extends RuntimeExceptionB {
private static final long serialVersionUID = 1L;
}
private class GoodRuntimeExceptionAMapper implements
ExceptionMapper<RuntimeExceptionA> {
@Override
public Response toResponse(RuntimeExceptionA exception) {
// TODO Auto-generated method stub
return null;
}
}
private class GoodRuntimeExceptionBMapper implements
ExceptionMapper<RuntimeExceptionB> {
@Override
public Response toResponse(RuntimeExceptionB exception) {
// TODO Auto-generated method stub
return null;
}
}
/**
* The parent implements ExceptionMapper and as a result will be what the
ProviderFactory.Comparator class incorrectly chooses when sort ordering
* the mappers rather than its children
*
*/
private abstract class BadParentExceptionMapper<T extends Throwable>
implements ExceptionMapper<T> {
}
/**
* This does not implement ExceptionMapper and so its parent will be
incorrectly selected by he ProviderFactory.Comparator class for sort
ordering
*
*/
@Provider
private class BadExceptionMapperA extends
BadParentExceptionMapper<RuntimeExceptionA> {
@Override
public Response toResponse(RuntimeExceptionA exception) {
return null;
}
}
/**
* This does not implement ExceptionMapper and so its parent will be
incorrectly selected by he ProviderFactory.Comparator class for sort
ordering
*
*/
@Provider
private class BadExceptionMapperB extends
BadParentExceptionMapper<RuntimeExceptionB> {
@Override
public Response toResponse(RuntimeExceptionB exception) {
return null;
}
}
/**
* This does NOT implement ExceptionMapper
*
*/
private abstract class FixedParentExceptionMapper {
}
/**
* The mapper implements ExceptionMapper directly
*
*/
@Provider
private class FixedExceptionMapperA extends FixedParentExceptionMapper
implements ExceptionMapper<RuntimeExceptionA> {
@Override
public Response toResponse(RuntimeExceptionA exception) {
return null;
}
}
/**
* The mapper implements ExceptionMapper directly
*
*/
@Provider
private class FixedExceptionMapperB extends FixedParentExceptionMapper
implements ExceptionMapper<RuntimeExceptionB> {
@Override
public Response toResponse(RuntimeExceptionB exception) {
return null;
}
}
}
On Thu, Oct 23, 2014 at 4:30 PM, Lambert, Michael <
[email protected]> wrote:
Sergei,
Here is a test case that demonstrates the problem. Note that the only
difference between the good test and the bad test is that the mapper itself
is derived from a parent class. This test is based on cxf 2.7.11 but i
presume it will also work with 3.0 by swapping out the providerfactory
class with serviceproviderfactory.
package foo.test;
import static org.junit.Assert.*;
import javax.ws.rs.core.Response;
import javax.ws.rs.ext.ExceptionMapper;
import javax.ws.rs.ext.Provider;
import org.apache.cxf.jaxrs.provider.ProviderFactory;
import org.apache.cxf.message.MessageImpl;
public class ExceptionMapperTest {
@org.junit.Before
public void setup() {
ProviderFactory.getInstance().clearProviders();
}
@org.junit.Test
public void testBadCustomExceptionMappersHierarchyWithGenerics() throws
Exception {
ProviderFactory pf = ProviderFactory.getInstance();
BadExceptionMapperA badExceptionMapperA = new BadExceptionMapperA();
pf.registerUserProvider(badExceptionMapperA);
BadExceptionMapperB badExceptionMapperB = new BadExceptionMapperB();
pf.registerUserProvider(badExceptionMapperB);
Object mapperResponse1 =
pf.createExceptionMapper(RuntimeExceptionA.class, new MessageImpl());
assertSame(badExceptionMapperA, mapperResponse1);
Object mapperResponse2 =
pf.createExceptionMapper(RuntimeExceptionB.class, new MessageImpl());
assertSame(badExceptionMapperB, mapperResponse2);
Object mapperResponse3 =
pf.createExceptionMapper(RuntimeExceptionAA.class, new MessageImpl());
assertSame(badExceptionMapperA, mapperResponse3);
Object mapperResponse4 =
pf.createExceptionMapper(RuntimeExceptionBB.class, new MessageImpl());
assertSame(badExceptionMapperB, mapperResponse4);
}
@org.junit.Test
public void testGoodExceptionMappersHierarchyWithGenerics() throws
Exception {
ProviderFactory pf = ProviderFactory.getInstance();
GoodRuntimeExceptionAMapper runtimeExceptionAMapper = new
GoodRuntimeExceptionAMapper();
pf.registerUserProvider(runtimeExceptionAMapper);
GoodRuntimeExceptionBMapper runtimeExceptionBMapper = new
GoodRuntimeExceptionBMapper();
pf.registerUserProvider(runtimeExceptionBMapper);
Object mapperResponse1 =
pf.createExceptionMapper(RuntimeExceptionA.class, new MessageImpl());
assertSame(runtimeExceptionAMapper, mapperResponse1);
Object mapperResponse2 =
pf.createExceptionMapper(RuntimeExceptionB.class, new MessageImpl());
assertSame(runtimeExceptionBMapper, mapperResponse2);
Object mapperResponse3 =
pf.createExceptionMapper(RuntimeExceptionAA.class, new MessageImpl());
assertSame(runtimeExceptionAMapper, mapperResponse3);
Object mapperResponse4 =
pf.createExceptionMapper(RuntimeExceptionBB.class, new MessageImpl());
assertSame(runtimeExceptionBMapper, mapperResponse4);
}
private class RuntimeExceptionA extends RuntimeException {
private static final long serialVersionUID = 1L;
}
private class RuntimeExceptionAA extends RuntimeExceptionA {
private static final long serialVersionUID = 1L;
}
private class RuntimeExceptionB extends RuntimeException {
private static final long serialVersionUID = 1L;
}
private class RuntimeExceptionBB extends RuntimeExceptionB {
private static final long serialVersionUID = 1L;
}
private class GoodRuntimeExceptionAMapper implements
ExceptionMapper<RuntimeExceptionA> {
@Override
public Response toResponse(RuntimeExceptionA exception) {
// TODO Auto-generated method stub
return null;
}
}
private class GoodRuntimeExceptionBMapper implements
ExceptionMapper<RuntimeExceptionB> {
@Override
public Response toResponse(RuntimeExceptionB exception) {
// TODO Auto-generated method stub
return null;
}
}
public abstract class BadParentExceptionMapper<T extends Throwable>
implements ExceptionMapper<T> {
}
@Provider
public class BadExceptionMapperA extends
BadParentExceptionMapper<RuntimeExceptionA> {
@Override
public Response toResponse(RuntimeExceptionA exception) {
return null;
}
}
@Provider
public class BadExceptionMapperB extends
BadParentExceptionMapper<RuntimeExceptionB> {
@Override
public Response toResponse(RuntimeExceptionB exception) {
return null;
}
}
}
On Wed, Oct 22, 2014 at 8:06 AM, Lambert, Michael <
[email protected]> wrote:
Good to know Sergey we will look at it again today. Definitely
experiencing the behavior I described so we will look for some delta
between our code and the test
On Oct 22, 2014 5:50 AM, "Sergey Beryozkin" <[email protected]>
wrote:
ProviderFactoryTest has the following:
private static class RuntimeExceptionMapper1
extends AbstractTestExceptionMapper<RuntimeException> {
}
private static class RuntimeExceptionMapper2
extends AbstractTestExceptionMapper<WebApplicationException> {
}
private static class AbstractTestExceptionMapper<T extends
RuntimeException>
implements ExceptionMapper<T> {
public Response toResponse(T arg0) {
// TODO Auto-generated method stub
return null;
}
}
This is identical to your example where you say the bug is expected,
also note WebApplicationException is RuntimeException.
@Test
public void testExceptionMappersHierarchyWithGenerics() throws
Exception {
ServerProviderFactory pf = ServerProviderFactory.getInstance();
RuntimeExceptionMapper1 exMapper1 = new
RuntimeExceptionMapper1();
pf.registerUserProvider(exMapper1);
RuntimeExceptionMapper2 exMapper2 = new
RuntimeExceptionMapper2();
pf.registerUserProvider(exMapper2);
assertSame(exMapper1, pf.createExceptionMapper(RuntimeException.class,
new MessageImpl()));
Object webExMapper =
pf.createExceptionMapper(WebApplicationException.class,
new MessageImpl());
assertSame(exMapper2, webExMapper);
}
When RuntimeExceptionMapper2 is registered, RuntimeExceptionMapper1 is
not picked for WebApplicationException. Updating the test not to register
RuntimeExceptionMapper2 leads to RuntimeExceptionMapper1 being selected for
WebApplicationException.
Looks like it is all correct to me, may be the issue is there in 2.7.11
but def not on the trunk/3.0.2
Cheers, Sergey
On 21/10/14 20:04, Lambert, Michael wrote:
To be clear:
This bug will only manifest itself if two exception mapper are both
derived
from the same interface:
public class AbstractMapper<T extends Throwable> implements
ExceptionMapper<T> {
...
}
public class FooMapper extends AbstractMapper<FooException> {
...
}
// ProviderFactory.ClassComparator.compare will return "0" when
BarMapper is compared to FooMapper
public class BarMapper extends AbstractMapper<BarException> {
...
}
If each exception mapper instance is derived from a DIFFERENT INTERFACE
everything works fine:
public interface IFooMapper extends ExceptionMapper<FooException>
{
...
}
public class FooMapper extends implements IFooMapper {
...
}
public interface IBarMapper extends ExceptionMapper<BarException>
{
...
}
// ProviderFactory.ClassComparator.compare will return "1" or -1
when
BarMapper is compared to FooMapper
public class BarMapper extends implements IBarMapper {
...
}
On Tue, Oct 21, 2014 at 2:34 PM, Lambert, Michael <
[email protected]> wrote:
Guys... it looks like there is a bug in ProviderFactory$
ClassComparator.
Given two mappers it always ends up comparing them as if both mappers
were
ExceptionMapper<Throwable>. There must be a problem in the way the
interfaces and "actual types" are derived (which is done in the
InjectionUtils class).
-Mike
On Tue, Oct 21, 2014 at 1:24 PM, Lambert, Michael <
[email protected]> wrote:
Hello gentleman!
My impression was that when implementing ExceptionMapper that the
mapper
of the nearest superclass of an exception would be used if an exact
exceptionmapper match to the exception didnt exist.
For example if I created a FooException which extended BarException
I
would only have to create a BarExceptionMapper to catch and map both
types
of exceptions; the BarExceptionMapper would be used when a
FooException was
thrown.
The red hat docs seem to reinforce this opinion:
-
When any exception other than a WebApplicationException
exception, or
one of its subclasses, is thrown, the runtime will check for an
appropriate
exception mapper. An exception mapper is selected if it handles
the
specific exception thrown. If there is not an exception mapper
for the
specific exception that was thrown, the exception mapper for the
nearest
superclass of the exception is selected.
https://access.redhat.com/documentation/en-US/Red_Hat_
JBoss_Fuse/6.1/html/Apache_CXF_Development_Guide/files/
RESTExceptionMapper.html
The reality is different for us however. In fact, if we create a
custom
WebApplicationExceptionMapper ClientErrorExceptions are not caught
by the
mapper. CXF seems to default to attempt to use whichever Mapper is
the
first one we registered (e.g. if we defined a FooExceptionMapper and
registered it, CXF would attempt to use that and throw an error
rather than
try to use the WebApplicationExceptionMapper).
Can someone tell me what the expected behavior is? Is my question
clear?
We are using CXF version 2.7.11.
Thanks!
Mike
--
Sergey Beryozkin
Talend Community Coders
http://coders.talend.com/
Blog: http://sberyozkin.blogspot.com
