Generics - Compilation failure - incompatible types - cast to parent type from
method taking in subtype.
--------------------------------------------------------------------------------------------------------
Key: MNG-2657
URL: http://jira.codehaus.org/browse/MNG-2657
Project: Maven 2
Issue Type: Bug
Affects Versions: 2.0.4
Environment: Windows Xp and Ubuntu Linux. Standard x86 hardware.
Reporter: Kenny MacDermid
Maven will not compile classes in the following situation, although eclipse
will compile them fine:
These are the two classes that are the types maven is getting confused with:
public abstract class User {...}
public class Employee extends User {...}
A factory called EntityManager returns a generic typed Criteria:
public <T, U extends T> Criteria<T> createCriteria(Class<U> c) {
return new CriteriaImpl<T>(c);
}
This is being used in the Tests in the following way:
Criteria<User> criteria = em.createCriteria(Employee.class);
As I said, in eclipse this compiles fine, with no warnings. With maven I
receive the error message:
[INFO] Compilation failure
...UserTest.java:[59,51] incompatible types
found : ....Criteria<....Employee>
required: ....Criteria<....User>
The stack trace is as follows:
org.apache.maven.BuildFailureException: Compilation failure
at
org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:555)
at
org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalWithLifecycle(DefaultLifecycleExecutor.java:475)
at
org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoal(DefaultLifecycleExecutor.java:454)
at
org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalAndHandleFailures(DefaultLifecycleExecutor.java:306)
at
org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeTaskSegments(DefaultLifecycleExecutor.java:273)
at
org.apache.maven.lifecycle.DefaultLifecycleExecutor.execute(DefaultLifecycleExecutor.java:140)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:322)
at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:115)
at org.apache.maven.cli.MavenCli.main(MavenCli.java:256)
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:585)
at org.codehaus.classworlds.Launcher.launchEnhanced(Launcher.java:315)
at org.codehaus.classworlds.Launcher.launch(Launcher.java:255)
at org.codehaus.classworlds.Launcher.mainWithExitCode(Launcher.java:430)
at org.codehaus.classworlds.Launcher.main(Launcher.java:375)
Caused by: org.apache.maven.plugin.CompilationFailureException: Compilation
failure
at
org.apache.maven.plugin.AbstractCompilerMojo.execute(AbstractCompilerMojo.java:505)
at
org.apache.maven.plugin.TestCompilerMojo.execute(TestCompilerMojo.java:99)
at
org.apache.maven.plugin.DefaultPluginManager.executeMojo(DefaultPluginManager.java:412)
at
org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:534)
... 16 more
Other possible useful maven information (actualy dir replaced with DIR):
[DEBUG] Configuring mojo
'org.apache.maven.plugins:maven-compiler-plugin:2.0.1:testCompile' -->
[DEBUG] (f) basedir = DIR
[DEBUG] (f) buildDirectory = DIR\target
[DEBUG] (f) classpathElements = [DIR\target\classes, DIR\target\test-classes,
... (many others)]
[DEBUG] (f) compileSourceRoots = [DIR\src\test\java]
[DEBUG] (f) compilerId = javac
[DEBUG] (f) debug = true
[DEBUG] (f) fork = false
[DEBUG] (f) optimize = false
[DEBUG] (f) outputDirectory = DIR\target\test-classes
[DEBUG] (f) outputFileName = IdentityRepository-0.1
[DEBUG] (f) showDeprecation = false
[DEBUG] (f) showWarnings = false
[DEBUG] (f) source = 1.5
[DEBUG] (f) staleMillis = 0
[DEBUG] (f) target = 1.5
[DEBUG] (f) verbose = false
[DEBUG] -- end configuration --
Thanks in advance,
Kenny
--
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators:
http://jira.codehaus.org/secure/Administrators.jspa
-
For more information on JIRA, see: http://www.atlassian.com/software/jira
