co.cask.cdap.internal.app.runtime.artifact.ArtifactClassLoaderFactory.java Source code

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Here is the source code for co.cask.cdap.internal.app.runtime.artifact.ArtifactClassLoaderFactory.java

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/*
 * Copyright  2015 Cask Data, Inc.
 *
 * 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 co.cask.cdap.internal.app.runtime.artifact;

import co.cask.cdap.common.lang.ProgramClassLoader;
import co.cask.cdap.common.lang.jar.BundleJarUtil;
import co.cask.cdap.common.utils.DirUtils;
import com.google.common.io.Closeables;
import org.apache.twill.filesystem.Location;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.Closeable;
import java.io.File;
import java.io.IOException;

/**
 * Given an artifact, creates a {@link CloseableClassLoader} from it. Takes care of unpacking the artifact and
 * cleaning up the directory when the classloader is closed.
 */
class ArtifactClassLoaderFactory {
    private static final Logger LOG = LoggerFactory.getLogger(ArtifactClassLoaderFactory.class);
    private final File baseUnpackDir;

    ArtifactClassLoaderFactory(File baseUnpackDir) {
        this.baseUnpackDir = baseUnpackDir;
    }

    CloseableClassLoader createClassLoader(Location artifactLocation) throws IOException {
        final File unpackDir = DirUtils.createTempDir(baseUnpackDir);
        BundleJarUtil.unpackProgramJar(artifactLocation, unpackDir);
        final ProgramClassLoader programClassLoader = ProgramClassLoader.create(unpackDir,
                getClass().getClassLoader());
        return new CloseableClassLoader(programClassLoader, new Closeable() {
            @Override
            public void close() {
                try {
                    Closeables.closeQuietly(programClassLoader);
                    DirUtils.deleteDirectoryContents(unpackDir);
                } catch (IOException e) {
                    LOG.warn("Failed to delete directory {}", unpackDir, e);
                }
            }
        });
    }
}