NEW - bug 371984: [api] provide a generic storage API

https://bugs.eclipse.org/bugs/show_bug.cgi?id=371984

Change-Id: I25a6b48962d68b40c5702d9100f92eed60165350

9 files changed, 433 insertions, 0 deletions

diff --git a/org.eclipse.mylyn.commons.core/META-INF/MANIFEST.MF b/org.eclipse.mylyn.commons.core/META-INF/MANIFEST.MF
index 6a3e5567..f0b38801 100644
--- a/org.eclipse.mylyn.commons.core/META-INF/MANIFEST.MF
+++ b/org.eclipse.mylyn.commons.core/META-INF/MANIFEST.MF
@@ -9,6 +9,7 @@ Export-Package: org.eclipse.mylyn.commons.core,
  org.eclipse.mylyn.commons.core.io,
  org.eclipse.mylyn.commons.core.net,
  org.eclipse.mylyn.commons.core.operations,
+ org.eclipse.mylyn.commons.core.storage;x-internal:=true,
  org.eclipse.mylyn.internal.commons.core;x-internal:=true,
  org.eclipse.mylyn.internal.commons.core.operations;x-internal:=true,
  org.eclipse.mylyn.internal.provisional.commons.core;x-internal:=true
diff --git a/org.eclipse.mylyn.commons.core/src/org/eclipse/mylyn/commons/core/CoreUtil.java b/org.eclipse.mylyn.commons.core/src/org/eclipse/mylyn/commons/core/CoreUtil.java
index 96c26ec3..cfc56ce5 100644
--- a/org.eclipse.mylyn.commons.core/src/org/eclipse/mylyn/commons/core/CoreUtil.java
+++ b/org.eclipse.mylyn.commons.core/src/org/eclipse/mylyn/commons/core/CoreUtil.java
@@ -219,4 +219,22 @@ public class CoreUtil {
 		return new Version(FRAMEWORK_VERSION);
 	}
 
+	/**
+	 * Returns a representation of <code>name</code> that is a valid file name.
+	 * 
+	 * @since 3.7
+	 */
+	public static String asFileName(String name) {
+		StringBuffer sb = new StringBuffer(name.length());
+		char[] chars = name.toCharArray();
+		for (char c : chars) {
+			if (c >= '0' && c <= '9' || c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z' || c == '.') {
+				sb.append(c);
+			} else {
+				sb.append("%" + Integer.toHexString(c).toUpperCase()); //$NON-NLS-1$
+			}
+		}
+		return sb.toString();
+	}
+
 }
diff --git a/org.eclipse.mylyn.commons.core/src/org/eclipse/mylyn/commons/core/storage/CommonStorable.java b/org.eclipse.mylyn.commons.core/src/org/eclipse/mylyn/commons/core/storage/CommonStorable.java
new file mode 100644
index 00000000..ae14eed0
--- /dev/null
+++ b/org.eclipse.mylyn.commons.core/src/org/eclipse/mylyn/commons/core/storage/CommonStorable.java
@@ -0,0 +1,85 @@
+/*******************************************************************************
+ * Copyright (c) 2012 Tasktop Technologies and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Tasktop Technologies - initial API and implementation
+ *******************************************************************************/
+
+package org.eclipse.mylyn.commons.core.storage;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+import org.eclipse.core.runtime.CoreException;
+import org.eclipse.core.runtime.IProgressMonitor;
+import org.eclipse.core.runtime.IStatus;
+import org.eclipse.core.runtime.Status;
+
+/**
+ * @author Steffen Pingel
+ */
+class CommonStorable implements ICommonStorable {
+
+	private final File path;
+
+	private final CommonStore store;
+
+	public CommonStorable(CommonStore store, File path) {
+		this.store = store;
+		this.path = path;
+	}
+
+	public void delete(String item) throws CoreException {
+		getFile(item).delete();
+	}
+
+	public boolean exists(String handle) {
+		if (!path.exists()) {
+			return false;
+		}
+		return getFile(handle).exists();
+	}
+
+	public IStatus flush() {
+		return Status.OK_STATUS;
+	}
+
+	public File getPath() {
+		return path;
+	}
+
+	public boolean isDirty() {
+		return false;
+	}
+
+	public InputStream read(String item, IProgressMonitor monitor) throws IOException {
+		File file = getFile(item);
+		return new FileInputStream(file);
+	}
+
+	public void release() {
+		store.release(this);
+	}
+
+	public OutputStream write(String item, IProgressMonitor monitor) throws IOException {
+		File file = getFile(item);
+		return new FileOutputStream(file);
+	}
+
+	private File getFile(String item) {
+		File file = new File(path, item);
+		if (!file.getParentFile().exists()) {
+			file.getParentFile().mkdirs();
+		}
+		return file;
+	}
+
+}
diff --git a/org.eclipse.mylyn.commons.core/src/org/eclipse/mylyn/commons/core/storage/CommonStore.java b/org.eclipse.mylyn.commons.core/src/org/eclipse/mylyn/commons/core/storage/CommonStore.java
new file mode 100644
index 00000000..3b7f09f2
--- /dev/null
+++ b/org.eclipse.mylyn.commons.core/src/org/eclipse/mylyn/commons/core/storage/CommonStore.java
@@ -0,0 +1,135 @@
+/*******************************************************************************
+ * Copyright (c) 2012 Tasktop Technologies and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Tasktop Technologies - initial API and implementation
+ *******************************************************************************/
+
+package org.eclipse.mylyn.commons.core.storage;
+
+import java.io.File;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.eclipse.core.runtime.Assert;
+import org.eclipse.core.runtime.IPath;
+import org.eclipse.core.runtime.IProgressMonitor;
+import org.eclipse.core.runtime.IStatus;
+import org.eclipse.core.runtime.MultiStatus;
+import org.eclipse.core.runtime.Status;
+import org.eclipse.core.runtime.jobs.Job;
+import org.eclipse.mylyn.commons.core.StatusHandler;
+import org.eclipse.mylyn.internal.commons.core.CommonsCorePlugin;
+
+/**
+ * @author Steffen Pingel
+ */
+public class CommonStore {
+
+	/**
+	 * Delays writing of mementos to avoid blocking UI thread.
+	 */
+	private class FlushJob extends Job {
+
+		public FlushJob() {
+			super("Flush context mementos"); //$NON-NLS-1$
+			setSystem(true);
+			setPriority(Job.SHORT);
+		}
+
+		@Override
+		protected IStatus run(IProgressMonitor monitor) {
+			flushPending();
+			return Status.OK_STATUS;
+		}
+
+	}
+
+	private static final long FLUSH_DELAY = 500;
+
+	private boolean scheduled;
+
+	private FlushJob flushJob;
+
+	private final Map<File, CommonStorable> storableByLocation;
+
+	private File location;
+
+	public CommonStore(File location) {
+		Assert.isNotNull(location);
+		this.storableByLocation = new HashMap<File, CommonStorable>();
+		this.location = location;
+	}
+
+	public synchronized ICommonStorable get(IPath path) {
+		File file = getFile(path);
+		CommonStorable storable = storableByLocation.get(file);
+		if (storable == null) {
+			storable = new CommonStorable(this, file);
+			storableByLocation.put(file, storable);
+		}
+		return storable;
+	}
+
+	public synchronized void copy(IPath source, IPath target, boolean overwrite) {
+		// FIXME
+	}
+
+	public File getLocation() {
+		return location;
+	}
+
+	public void setLocation(File location) {
+		Assert.isNotNull(location);
+		this.location = location;
+	}
+
+	public void stop() {
+		synchronized (this) {
+			if (flushJob != null) {
+				flushJob.cancel();
+				flushJob = null;
+			}
+		}
+		flushPending();
+	}
+
+	private File getFile(IPath path) {
+		File file = new File(location, path.toOSString());
+		if (!file.getParentFile().exists()) {
+			file.getParentFile().mkdirs();
+		}
+		return file;
+	}
+
+	synchronized void schedule() {
+		if (!scheduled) {
+			if (flushJob == null) {
+				flushJob = new FlushJob();
+			}
+			flushJob.schedule(FLUSH_DELAY);
+		}
+	}
+
+	synchronized void flushPending() {
+		MultiStatus status = new MultiStatus(CommonsCorePlugin.ID_PLUGIN, 0, "Failed to save storable", null); //$NON-NLS-1$
+		for (CommonStorable memento : storableByLocation.values()) {
+			if (memento.isDirty()) {
+				IStatus result = memento.flush();
+				status.add(result);
+			}
+		}
+		if (!status.isOK()) {
+			StatusHandler.log(status);
+		}
+	}
+
+	synchronized void release(CommonStorable storable) {
+		storableByLocation.remove(storable.getPath());
+	}
+
+}
diff --git a/org.eclipse.mylyn.commons.core/src/org/eclipse/mylyn/commons/core/storage/ICommonStorable.java b/org.eclipse.mylyn.commons.core/src/org/eclipse/mylyn/commons/core/storage/ICommonStorable.java
new file mode 100644
index 00000000..dc5bedbe
--- /dev/null
+++ b/org.eclipse.mylyn.commons.core/src/org/eclipse/mylyn/commons/core/storage/ICommonStorable.java
@@ -0,0 +1,36 @@
+/*******************************************************************************
+ * Copyright (c) 2012 Tasktop Technologies and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Tasktop Technologies - initial API and implementation
+ *******************************************************************************/
+
+package org.eclipse.mylyn.commons.core.storage;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+import org.eclipse.core.runtime.CoreException;
+import org.eclipse.core.runtime.IProgressMonitor;
+
+/**
+ * @author Steffen Pingel
+ */
+public interface ICommonStorable {
+
+	public void delete(String handle) throws CoreException;
+
+	public boolean exists(String handle);
+
+	public InputStream read(String handle, IProgressMonitor monitor) throws IOException, CoreException;
+
+	public OutputStream write(String handle, IProgressMonitor monitor) throws IOException, CoreException;
+
+	public void release();
+
+}
diff --git a/org.eclipse.mylyn.commons.sdk.util/src/org/eclipse/mylyn/commons/sdk/util/CommonTestUtil.java b/org.eclipse.mylyn.commons.sdk.util/src/org/eclipse/mylyn/commons/sdk/util/CommonTestUtil.java
index 41e10861..bb52cc00 100644
--- a/org.eclipse.mylyn.commons.sdk.util/src/org/eclipse/mylyn/commons/sdk/util/CommonTestUtil.java
+++ b/org.eclipse.mylyn.commons.sdk.util/src/org/eclipse/mylyn/commons/sdk/util/CommonTestUtil.java
@@ -122,6 +122,13 @@ public class CommonTestUtil {
 		return stateLocation.toFile();
 	}
 
+	public static File createTempFolder(String prefix) throws IOException {
+		File location = File.createTempFile(prefix, null);
+		location.delete();
+		location.mkdirs();
+		return location;
+	}
+
 	public static void delete(File file) {
 		if (file.exists()) {
 			for (int i = 0; i < MAX_RETRY; i++) {
@@ -158,6 +165,7 @@ public class CommonTestUtil {
 				}
 			}
 		}
+		path.delete();
 	}
 
 	public static CertificateCredentials getCertificateCredentials() {
diff --git a/org.eclipse.mylyn.commons.tests/src/org/eclipse/mylyn/commons/tests/AllCommonsTests.java b/org.eclipse.mylyn.commons.tests/src/org/eclipse/mylyn/commons/tests/AllCommonsTests.java
index 1f4210df..9eb53986 100644
--- a/org.eclipse.mylyn.commons.tests/src/org/eclipse/mylyn/commons/tests/AllCommonsTests.java
+++ b/org.eclipse.mylyn.commons.tests/src/org/eclipse/mylyn/commons/tests/AllCommonsTests.java
@@ -18,6 +18,7 @@ import org.eclipse.mylyn.commons.tests.core.AuthenticatedProxyTest;
 import org.eclipse.mylyn.commons.tests.core.CommonListenerListTest;
 import org.eclipse.mylyn.commons.tests.core.CoreUtilTest;
 import org.eclipse.mylyn.commons.tests.core.ExtensionPointReaderTest;
+import org.eclipse.mylyn.commons.tests.core.storage.CommonStoreTest;
 import org.eclipse.mylyn.commons.tests.net.NetUtilTest;
 import org.eclipse.mylyn.commons.tests.net.SslProtocolSocketFactoryTest;
 import org.eclipse.mylyn.commons.tests.net.TimeoutInputStreamTest;
@@ -42,6 +43,7 @@ public class AllCommonsTests {
 		suite.addTestSuite(BrowserUtilTest.class);
 		suite.addTestSuite(ExtensionPointReaderTest.class);
 		suite.addTestSuite(CommonListenerListTest.class);
+		suite.addTestSuite(CommonStoreTest.class);
 		return suite;
 	}
 
diff --git a/org.eclipse.mylyn.commons.tests/src/org/eclipse/mylyn/commons/tests/core/CoreUtilTest.java b/org.eclipse.mylyn.commons.tests/src/org/eclipse/mylyn/commons/tests/core/CoreUtilTest.java
index a729f9b3..aec0326b 100644
--- a/org.eclipse.mylyn.commons.tests/src/org/eclipse/mylyn/commons/tests/core/CoreUtilTest.java
+++ b/org.eclipse.mylyn.commons.tests/src/org/eclipse/mylyn/commons/tests/core/CoreUtilTest.java
@@ -184,4 +184,20 @@ public class CoreUtilTest extends TestCase {
 		}
 	}
 
+	public void testAsFileName() {
+		assertEquals("abc", CoreUtil.asFileName("abc"));
+		assertEquals("a.b.c", CoreUtil.asFileName("a.b.c"));
+		assertEquals("", CoreUtil.asFileName(""));
+	}
+
+	public void testAsFileNameSpaces() {
+		assertEquals("%20%20", CoreUtil.asFileName("  "));
+		assertEquals(".%20", CoreUtil.asFileName(". "));
+	}
+
+	public void testAsFileNamePercent() {
+		assertEquals("%25abc", CoreUtil.asFileName("%abc"));
+		assertEquals("%2525abc", CoreUtil.asFileName("%25abc"));
+	}
+
 }
diff --git a/org.eclipse.mylyn.commons.tests/src/org/eclipse/mylyn/commons/tests/core/storage/CommonStoreTest.java b/org.eclipse.mylyn.commons.tests/src/org/eclipse/mylyn/commons/tests/core/storage/CommonStoreTest.java
new file mode 100644
index 00000000..eb11e304
--- /dev/null
+++ b/org.eclipse.mylyn.commons.tests/src/org/eclipse/mylyn/commons/tests/core/storage/CommonStoreTest.java
@@ -0,0 +1,132 @@
+/*******************************************************************************
+ * Copyright (c) 2012 Tasktop Technologies and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Tasktop Technologies - initial API and implementation
+ *******************************************************************************/
+
+package org.eclipse.mylyn.commons.tests.core.storage;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.Arrays;
+import java.util.Collections;
+
+import junit.framework.TestCase;
+
+import org.eclipse.core.runtime.CoreException;
+import org.eclipse.core.runtime.Path;
+import org.eclipse.mylyn.commons.core.storage.CommonStore;
+import org.eclipse.mylyn.commons.core.storage.ICommonStorable;
+import org.eclipse.mylyn.commons.sdk.util.CommonTestUtil;
+
+/**
+ * @author Steffen Pingel
+ */
+public class CommonStoreTest extends TestCase {
+
+	private File location;
+
+	private CommonStore store;
+
+	public void testDelete() throws Exception {
+		ICommonStorable storable = store.get(Path.EMPTY);
+		assertFalse(storable.exists("handle"));
+
+		OutputStream out = storable.write("handle", null);
+		out.close();
+		assertTrue(storable.exists("handle"));
+		assertEquals(Collections.singletonList(new File(location, "handle")), Arrays.asList(location.listFiles()));
+
+		storable.delete("handle");
+		assertFalse(storable.exists("handle"));
+		assertEquals(Collections.emptyList(), Arrays.asList(location.listFiles()));
+	}
+
+	public void testExists() throws Exception {
+		ICommonStorable storable = store.get(Path.EMPTY);
+		assertFalse(storable.exists("handle"));
+
+		OutputStream out = storable.write("handle", null);
+		out.close();
+		assertTrue(storable.exists("handle"));
+	}
+
+	public void testGetPathWrite() throws Exception {
+		ICommonStorable storable = store.get(new Path("sub"));
+		writeHello(storable, "handle");
+		File subFile = new File(location, "sub");
+		assertEquals(Collections.singletonList(subFile), Arrays.asList(location.listFiles()));
+		assertEquals(Collections.singletonList(new File(subFile, "handle")), Arrays.asList(subFile.listFiles()));
+	}
+
+	public void testGet() throws Exception {
+		ICommonStorable storable = store.get(Path.EMPTY);
+		ICommonStorable storable2 = store.get(Path.EMPTY);
+		assertSame(storable, storable2);
+	}
+
+	public void testGetPath() {
+		ICommonStorable storable = store.get(new Path("sub"));
+		ICommonStorable storable2 = store.get(Path.EMPTY);
+		assertNotSame(storable, storable2);
+		storable2 = store.get(new Path("sub"));
+		assertSame(storable, storable2);
+	}
+
+	public void testGetPathLazyCreate() {
+		ICommonStorable storable = store.get(new Path("sub"));
+		assertEquals(Collections.emptyList(), Arrays.asList(location.listFiles()));
+		assertFalse(storable.exists("handle"));
+		assertEquals(Collections.emptyList(), Arrays.asList(location.listFiles()));
+	}
+
+	public void testRelease() throws Exception {
+		ICommonStorable storable = store.get(Path.EMPTY);
+		storable.release();
+		ICommonStorable storable2 = store.get(Path.EMPTY);
+		assertNotSame(storable, storable2);
+	}
+
+	public void testWriteRead() throws Exception {
+		ICommonStorable storable = store.get(Path.EMPTY);
+		writeHello(storable, "handle");
+		assertTrue(storable.exists("handle"));
+
+		InputStream in = storable.read("handle", null);
+		try {
+			byte[] buffer = new byte[5];
+			in.read(buffer);
+			assertEquals("hello", new String(buffer));
+		} finally {
+			in.close();
+		}
+	}
+
+	private void writeHello(ICommonStorable storable, String handle) throws IOException, CoreException {
+		OutputStream out = storable.write(handle, null);
+		try {
+			out.write("hello".getBytes());
+		} finally {
+			out.close();
+		}
+	}
+
+	@Override
+	protected void setUp() throws Exception {
+		location = CommonTestUtil.createTempFolder(CommonStoreTest.class.getName());
+		store = new CommonStore(location);
+	}
+
+	@Override
+	protected void tearDown() throws Exception {
+		CommonTestUtil.deleteFolderRecursively(location);
+	}
+
+}