jcommons/org.eclipse.statet.jcommons.util/src/org/eclipse/statet/jcommons/runtime/bundle/BundleEntryProvider.java

/*=============================================================================#
 # Copyright (c) 2018, 2020 Stephan Wahlbrink and others.
 # 
 # This program and the accompanying materials are made available under the
 # terms of the Eclipse Public License 2.0 which is available at
 # https://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
 # which is available at https://www.apache.org/licenses/LICENSE-2.0.
 # 
 # SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
 # 
 # Contributors:
 #     Stephan Wahlbrink <sw@wahlbrink.eu> - initial API and implementation
 #=============================================================================*/

package org.eclipse.statet.jcommons.runtime.bundle;

import static org.eclipse.statet.internal.jcommons.runtime.CommonsRuntimeInternals.BUNDLE_ID;
import static org.eclipse.statet.jcommons.lang.ObjectUtils.nonNullAssert;
import static org.eclipse.statet.jcommons.runtime.CommonsRuntime.log;

import java.io.Closeable;
import java.io.IOException;
import java.nio.file.DirectoryStream;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.eclipse.statet.jcommons.collections.ImCollections;
import org.eclipse.statet.jcommons.collections.ImList;
import org.eclipse.statet.jcommons.lang.NonNullByDefault;
import org.eclipse.statet.jcommons.lang.Nullable;
import org.eclipse.statet.jcommons.lang.ObjectUtils.ToStringBuilder;
import org.eclipse.statet.jcommons.status.ErrorStatus;


@NonNullByDefault
public abstract class BundleEntryProvider {
	
	
	public static class JarFilePathEntryProvider extends BundleEntryProvider {
		
		
		private final Pattern namePattern;
		
		
		public JarFilePathEntryProvider(final ImList<Path> baseDirectories, final Pattern namePattern,
				final List<Closeable> closeables) {
			super(baseDirectories, closeables);
			this.namePattern= namePattern;
		}
		
		public JarFilePathEntryProvider(final Path baseDirectory, final Pattern namePattern,
				final List<Closeable> closeables) {
			this(ImCollections.newList(nonNullAssert(baseDirectory)), namePattern, closeables);
		}
		
		
		@Override
		protected @Nullable BundleEntry createEntry(final Path candidate) {
			final Matcher nameMatcher= this.namePattern.matcher(
					nonNullAssert(candidate.getFileName()).toString() );
			if (nameMatcher.matches() && Files.isRegularFile(candidate)) {
				final String bundleId= nonNullAssert(nameMatcher.group(1));
				return new BundleEntry.Jar(bundleId, candidate);
			}
			return null;
		}
		
		/** for tests */
		@Nullable String getBundleId(final String fileName) {
			final Matcher nameMatcher= this.namePattern.matcher(fileName);
			if (nameMatcher.matches()) {
				return nameMatcher.group(1);
			}
			return null;
		}
		
		
		@Override
		public int hashCode() {
			return super.hashCode() + this.namePattern.hashCode() * 17;
		}
		
		@Override
		public boolean equals(final @Nullable Object obj) {
			return (super.equals(obj)
					&& this.namePattern.pattern().equals(((JarFilePathEntryProvider) obj).namePattern.pattern()) );
		}
		
		@Override
		public String toString() {
			final ToStringBuilder sb= new ToStringBuilder("JarFileBundleEntryProvider", getClass()); //$NON-NLS-1$
			sb.addProp("baseDirectories", getBaseDirectories()); //$NON-NLS-1$
			sb.addProp("namePattern", this.namePattern); //$NON-NLS-1$
			return sb.toString();
		}
		
	}
	
	public static class DevBinPathEntryProvider extends BundleEntryProvider {
		
		
		public DevBinPathEntryProvider(final ImList<Path> baseDirectories,
				final List<Closeable> closeables) {
			super(baseDirectories, closeables);
		}
		
		public DevBinPathEntryProvider(final Path baseDirectory,
				final List<Closeable> closeables) {
			this(ImCollections.newList(nonNullAssert(baseDirectory)), closeables);
		}
		
		
		@Override
		protected @Nullable BundleEntry createEntry(final Path candidate) {
			final Path devBin;
			if (Files.isDirectory(devBin= candidate.resolve("target/classes"))) { //$NON-NLS-1$
				final String bundleId= nonNullAssert(candidate.getFileName()).toString();
				return new BundleEntry.Dir(bundleId, candidate, devBin);
			}
			return null;
		}
		
		@Override
		public String toString() {
			final ToStringBuilder sb= new ToStringBuilder("DevBinPathEntryProvider", getClass()); //$NON-NLS-1$
			sb.addProp("baseDirectories", getBaseDirectories()); //$NON-NLS-1$
			return sb.toString();
		}
		
	}
	
	
	private final ImList<Path> baseDirectories;
	
	private final List<Closeable> closeables;
	
	
	protected BundleEntryProvider(final ImList<Path> baseDirectories,
			final List<Closeable> closeables) {
		this.baseDirectories= baseDirectories;
		this.closeables= closeables;
	}
	
	public void dispose() {
		Bundles.close(this.closeables);
	}
	
	
	protected ImList<Path> getBaseDirectories() {
		return this.baseDirectories;
	}
	
	public void getEntries(final List<BundleEntry> entries) {
		for (final Path baseDirectory : this.baseDirectories) {
			try {
				getEntries(baseDirectory, entries);
			}
			catch (final Exception e) {
				log(new ErrorStatus(BUNDLE_ID,
						String.format("An error occurred when looking for path entries in '%1$s'.",
								baseDirectory ),
						e ));
			}
		}
	}
	
	protected void getEntries(final Path baseDirectory, final List<BundleEntry> entries)
			throws IOException {
		try (final DirectoryStream<Path> children= Files.newDirectoryStream(baseDirectory)) {
			for (final Path child : children) {
				final BundleEntry entry= createEntry(child);
				if (entry != null) {
					entries.add(entry);
				}
			}
		}
	}
	
	protected @Nullable BundleEntry createEntry(final Path candidate) {
		return null;
	}
	
	
	@Override
	public int hashCode() {
		return getClass().hashCode() + this.baseDirectories.hashCode();
	}
	
	@Override
	public boolean equals(final @Nullable Object obj) {
		if (this == obj) {
			return true;
		}
		if (obj != null && getClass() == obj.getClass()) {
			final BundleEntryProvider other= (BundleEntryProvider) obj;
			return (this.baseDirectories.equals(other.baseDirectories));
		}
		return false;
	}
	
}