added support for yaml serialization

src/io/protostuff/YamlIOUtil.java

@@ -0,0 +1,206 @@
+//========================================================================
+//Copyright 2007-2010 David Yu dyuproject@gmail.com
+//------------------------------------------------------------------------
+//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 io.protostuff;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.util.List;
+
+/**
+ * Utility for the YAML serialization of messages and objects tied to a schema.
+ * 
+ * @author David Yu
+ * @created Jun 28, 2010
+ */
+public final class YamlIOUtil
+{
+
+    private static final byte[] START_DIRECTIVE = new byte[] {
+            (byte) '-', (byte) '-', (byte) '-', (byte) ' '
+    };
+
+    /**
+     * Serializes the {@code message} into a byte array with the supplied buffer.
+     */
+    public static <T> byte[] toByteArray(T message, Schema<T> schema, LinkedBuffer buffer)
+    {
+        if (buffer.start != buffer.offset)
+            throw new IllegalArgumentException("Buffer previously used and had not been reset.");
+
+        final YamlOutput output = new YamlOutput(buffer, schema);
+
+        try
+        {
+            output.tail = YamlOutput.writeTag(
+                    schema.messageName(),
+                    false,
+                    output.sink,
+                    output,
+                    output.sink.writeByteArray(
+                            START_DIRECTIVE,
+                            output,
+                            buffer));
+
+            schema.writeTo(output, message);
+        }
+        catch (IOException e)
+        {
+            throw new RuntimeException("Serializing to a byte array threw an IOException " +
+                    "(should never happen).", e);
+        }
+
+        return output.toByteArray();
+    }
+
+    /**
+     * Serializes the {@code message} into the {@link LinkedBuffer}.
+     * 
+     * @return the total bytes written to the output.
+     */
+    public static <T> int writeTo(LinkedBuffer buffer, T message, Schema<T> schema)
+    {
+        if (buffer.start != buffer.offset)
+            throw new IllegalArgumentException("Buffer previously used and had not been reset.");
+
+        final YamlOutput output = new YamlOutput(buffer, schema);
+
+        try
+        {
+            output.tail = YamlOutput.writeTag(
+                    schema.messageName(),
+                    false,
+                    output.sink,
+                    output,
+                    output.sink.writeByteArray(
+                            START_DIRECTIVE,
+                            output,
+                            buffer));
+
+            schema.writeTo(output, message);
+        }
+        catch (IOException e)
+        {
+            throw new RuntimeException("Serializing to a LinkedBuffer threw an IOException " +
+                    "(should never happen).", e);
+        }
+
+        return output.getSize();
+    }
+
+    /**
+     * Serializes the {@code message} into an {@link OutputStream} with the supplied buffer.
+     * 
+     * @return the total bytes written to the output.
+     */
+    public static <T> int writeTo(OutputStream out, T message, Schema<T> schema,
+            LinkedBuffer buffer) throws IOException
+    {
+        if (buffer.start != buffer.offset)
+            throw new IllegalArgumentException("Buffer previously used and had not been reset.");
+
+        final YamlOutput output = new YamlOutput(buffer, out, schema);
+
+        output.tail = YamlOutput.writeTag(
+                schema.messageName(),
+                false,
+                output.sink,
+                output,
+                output.sink.writeByteArray(
+                        START_DIRECTIVE,
+                        output,
+                        buffer));
+
+        schema.writeTo(output, message);
+
+        LinkedBuffer.writeTo(out, buffer);
+
+        return output.getSize();
+    }
+
+    /**
+     * Serializes the {@code messages} a {@link LinkedBuffer} using the given schema.
+     * 
+     * @return the total bytes written to the output.
+     */
+    public static <T> int writeListTo(LinkedBuffer buffer, List<T> messages,
+            Schema<T> schema)
+    {
+        if (buffer.start != buffer.offset)
+            throw new IllegalArgumentException("Buffer previously used and had not been reset.");
+
+        final YamlOutput output = new YamlOutput(buffer, schema);
+
+        try
+        {
+            output.tail = YamlOutput.writeTag(
+                    schema.messageName(),
+                    true,
+                    output.sink,
+                    output,
+                    output.sink.writeByteArray(
+                            START_DIRECTIVE,
+                            output,
+                            buffer));
+
+            for (T m : messages)
+            {
+                schema.writeTo(output.writeSequenceDelim(), m);
+                output.reset();
+            }
+        }
+        catch (IOException e)
+        {
+            throw new RuntimeException("Serializing to a LinkedBuffer threw an IOException " +
+                    "(should never happen).", e);
+        }
+
+        return output.getSize();
+    }
+
+    /**
+     * Serializes the {@code messages} into an {@link OutputStream} using the given schema with the supplied buffer.
+     * 
+     * @return the total bytes written to the output.
+     */
+    public static <T> int writeListTo(OutputStream out, List<T> messages,
+            Schema<T> schema, LinkedBuffer buffer) throws IOException
+    {
+        if (buffer.start != buffer.offset)
+            throw new IllegalArgumentException("Buffer previously used and had not been reset.");
+
+        final YamlOutput output = new YamlOutput(buffer, out, schema);
+
+        output.tail = YamlOutput.writeTag(
+                schema.messageName(),
+                true,
+                output.sink,
+                output,
+                output.sink.writeByteArray(
+                        START_DIRECTIVE,
+                        output,
+                        buffer));
+
+        for (T m : messages)
+        {
+            schema.writeTo(output.writeSequenceDelim(), m);
+            output.reset();
+        }
+
+        LinkedBuffer.writeTo(out, buffer);
+
+        return output.getSize();
+    }
+
+}