Java API for mojo system.

mojo/public/java/src/org/chromium/mojo/system/SharedBufferHandle.java

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.mojo.system;
+
+import java.nio.ByteBuffer;
+
+/**
+ * A buffer that can be shared between applications.
+ */
+public interface SharedBufferHandle extends Handle {
+
+    /**
+     * Flags for the shared buffer creation operation.
+     */
+    public static class CreateFlags extends Flags<CreateFlags> {
+        private static final int FLAG_NONE = 0;
+
+        /**
+         * Dedicated constructor.
+         *
+         * @param flags initial value of the flags.
+         */
+        protected CreateFlags(int flags) {
+            super(flags);
+        }
+
+        /**
+         * @return flags with no bit set.
+         */
+        public static CreateFlags none() {
+            return new CreateFlags(FLAG_NONE);
+        }
+
+    }
+
+    /**
+     * Used to specify creation parameters for a shared buffer to |Core#createSharedBuffer()|.
+     */
+    public static class CreateOptions {
+        private CreateFlags mFlags = CreateFlags.none();
+
+        /**
+         * @return the flags
+         */
+        public CreateFlags getFlags() {
+            return mFlags;
+        }
+
+    }
+
+    /**
+     * Flags for the shared buffer duplication operation.
+     */
+    public static class DuplicateFlags extends Flags<DuplicateFlags> {
+        private static final int FLAG_NONE = 0;
+
+        /**
+         * Dedicated constructor.
+         *
+         * @param flags initial value of the flags.
+         */
+        protected DuplicateFlags(int flags) {
+            super(flags);
+        }
+
+        /**
+         * @return flags with no bit set.
+         */
+        public static DuplicateFlags none() {
+            return new DuplicateFlags(FLAG_NONE);
+        }
+
+    }
+
+    /**
+     * Used to specify parameters in duplicating access to a shared buffer to
+     * |SharedBufferHandle#duplicate|
+     */
+    public static class DuplicateOptions {
+        private DuplicateFlags mFlags = DuplicateFlags.none();
+
+        /**
+         * @return the flags
+         */
+        public DuplicateFlags getFlags() {
+            return mFlags;
+        }
+
+    }
+
+    /**
+     * TODO(qsr): Insert description here.
+     */
+    public static class MapFlags extends Flags<MapFlags> {
+        private static final int FLAG_NONE = 0;
+
+        /**
+         * Dedicated constructor.
+         *
+         * @param flags initial value of the flags.
+         */
+        protected MapFlags(int flags) {
+            super(flags);
+        }
+
+        /**
+         * @return flags with no bit set.
+         */
+        public static MapFlags none() {
+            return new MapFlags(FLAG_NONE);
+        }
+
+    }
+
+    /**
+     * Duplicates the handle. This creates another handle (returned on success), which can then be
+     * sent to another application over a message pipe, while retaining access to this handle (and
+     * any mappings that it may have).
+     */
+    public SharedBufferHandle duplicate(DuplicateOptions options);
+
+    /**
+     * Map the part (at offset |offset| of length |numBytes|) of the buffer given by this handle
+     * into memory. |offset + numBytes| must be less than or equal to the size of the buffer. On
+     * success, the returned buffer points to memory with the requested part of the buffer. A single
+     * buffer handle may have multiple active mappings (possibly depending on the buffer type). The
+     * permissions (e.g., writable or executable) of the returned memory may depend on the
+     * properties of the buffer and properties attached to the buffer handle as well as |flags|.
+     */
+    public ByteBuffer map(long offset, long numBytes, MapFlags flags);
+
+    /**
+     * Unmap a buffer pointer that was mapped by |map()|.
+     */
+    public void unmap(ByteBuffer buffer);
+
+}