/*
* Copyright 2009 the original author or authors.
*
* Licensed 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.gradle.openapi.external.runner;
import org.gradle.openapi.external.ExternalUtility;
import java.io.File;
import java.lang.reflect.Constructor;
/**
This provides a simple way to execute gradle commands from an external
process. call createGradleRunner to instantiate a gradle runner. You can then
use that to execute commands.
@author mhunsicker
*/
public class GradleRunnerFactory
{
/*
Call this to instantiate an object that you can use to execute gradle
commands directly.
Note: this function is meant to be backward and forward compatible. So
this signature should not change at all, however, it may take and return
objects that implement ADDITIONAL interfaces. That is, it will always
return a GradleRunnerVersion1, but it may also be an object that implements
GradleRunnerVersion2 (notice the 2). The caller will need to dynamically
determine that. The GradleRunnerInteractionVersion1 may take an object
that also implements GradleRunnerInteractionVersion2. If so, we'll
dynamically determine that and handle it. Of course, this all depends on
what happens in the future.
@param parentClassLoader Your classloader. Probably the classloader
of whatever class is calling this.
@param gradleHomeDirectory the root directory of a gradle installation
@param interaction this is how we interact with the caller.
@param showDebugInfo true to show some additional information that
may be helpful diagnosing problems is this
fails
@return a gradle runner
@author mhunsicker
*/
public static GradleRunnerVersion1 createGradleRunner( ClassLoader parentClassLoader, File gradleHomeDirectory, GradleRunnerInteractionVersion1 interaction, boolean showDebugInfo ) throws Exception
{
//much of this function is exception handling so if we can't obtain it via the newer factory method, then
//we'll try the old way, but we want to report the original exception if we can't do it either way.
Exception viaFactoryException = null;
GradleRunnerVersion1 gradleRunner = null;
//first, try it the new way
try {
gradleRunner = createGradleRunnerViaFactory(parentClassLoader, gradleHomeDirectory, interaction, showDebugInfo);
} catch (Exception e) {
//we might ignore this. It means we're probably using an older version of gradle. That case is handled below.
//If not, this exception will be thrown at the end.
viaFactoryException = e;
}
//try it the old way
if( gradleRunner == null ) {
gradleRunner = createGradleRunnerOldWay(parentClassLoader, gradleHomeDirectory, interaction, showDebugInfo);
}
//if we still don't have a gradle runner and we have an exception from using the factory, throw it. If we
//got an exception using the 'old way', it would have been thrown already and we wouldn't be here.
if( gradleRunner == null && viaFactoryException != null ) {
throw viaFactoryException;
}
return gradleRunner;
}
/**
* This function uses a factory to instantiate a GradleRunner. The factory is located with the version of gradle
* pointed to by gradleHomeDirectory and thus allows the version of gradle being loaded to make decisions
* about how to instantiate the runner. This is needed as multiple versions of the runner are being used.
*/
private static GradleRunnerVersion1 createGradleRunnerViaFactory( ClassLoader parentClassLoader, File gradleHomeDirectory, GradleRunnerInteractionVersion1 interaction, boolean showDebugInfo ) throws Exception
{
//load the class in gradle that wraps our return interface and handles versioning issues.
Class soughtClass = ExternalUtility.loadGradleClass( "org.gradle.openapi.wrappers.RunnerWrapperFactory", parentClassLoader, gradleHomeDirectory, showDebugInfo );
if( soughtClass == null )
{
return null;
}
Class[] argumentClasses = new Class[ ] { File.class, GradleRunnerInteractionVersion1.class, boolean.class };
Object gradleRunner = ExternalUtility.invokeStaticMethod( soughtClass, "createGradleRunner", argumentClasses, gradleHomeDirectory, interaction, showDebugInfo );
return (GradleRunnerVersion1) gradleRunner;
}
/**
* This function uses an early way (early 0.9 pre-release and sooner) of instantiating the GradleRunner and
* should no longer be used. It unfortunately is tied to a single wrapper class instance (which it tries to
* directly instantiate). This doesn't allow the GradleRunner to adaptively determine what to instantiate.
*/
private static GradleRunnerVersion1 createGradleRunnerOldWay( ClassLoader parentClassLoader, File gradleHomeDirectory, GradleRunnerInteractionVersion1 interaction, boolean showDebugInfo ) throws Exception
{
ClassLoader bootStrapClassLoader = ExternalUtility.getGradleClassloader( parentClassLoader, gradleHomeDirectory, showDebugInfo );
Thread.currentThread().setContextClassLoader(bootStrapClassLoader);
//load the class in gradle that wraps our return interface and handles versioning issues.
Class soughtClass = null;
try
{
soughtClass = bootStrapClassLoader.loadClass( "org.gradle.openapi.wrappers.runner.GradleRunnerWrapper" );
}
catch( NoClassDefFoundError e )
{ //might be a version mismatch
e.printStackTrace();
return null;
}
catch( ClassNotFoundException e )
{ //might be a version mismatch
e.printStackTrace();
return null;
}
if( soughtClass == null ) {
return null;
}
//instantiate it.
Constructor constructor = null;
try
{
constructor = soughtClass.getDeclaredConstructor( File.class, GradleRunnerInteractionVersion1.class );
}
catch( NoSuchMethodException e )
{
e.printStackTrace();
System.out.println( "Dumping available constructors on " + soughtClass.getName() + "\n" + ExternalUtility.dumpConstructors( soughtClass ) );
throw e;
}
Object gradleRunner = constructor.newInstance( gradleHomeDirectory, interaction );
return (GradleRunnerVersion1) gradleRunner;
}
}