Levels

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 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you 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 com.sun.jini.logging;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.ObjectStreamClass;
import java.io.ObjectStreamException;
import java.io.OutputStream;
import java.io.Serializable;
import java.util.logging.Level;
import org.apache.river.api.io.AtomicSerial;
import org.apache.river.api.io.AtomicSerial.GetArg;

/**
* Defines additional {@link Level} values.
*
* @since 2.0
*/
@Deprecated
public class Levels {

    /**
    * <p>
    * <code>FAILED</code> is a message level indicating that a facility has
    * experienced a failure that it will reflect to its caller. </p>
    * <p>
    * <code>FAILED</code> messages are intended to provide users with
    * information about failures produced by internal components in order to
    * assist with debugging problems in systems with multiple components. This
    * level is initialized to <code>600</code>.</p>
    */
    public static final Level FAILED = createLevel("FAILED", 600, null);

    /**
     * <p>
    * <code>HANDLED</code> is a message level indicating that a facility has
    * detected a failure that it will take steps to handle without reflecting
    * the failure to its caller. </p>
    * <p>
    * <code>HANDLED</code> messages are intended to provide users with
    * information about failures detected by internal components in order to
    * assist with debugging problems in systems with multiple components. This
    * level is initialized to <code>550</code>.</p>
    */
    public static final Level HANDLED = createLevel("HANDLED", 550, null);

    /**
    * This class cannot be instantiated.
    */
    private Levels() {
        throw new AssertionError("This class cannot be instantiated");
    }

    /**
    * Defines a class that has the same data format as the Level class, to
    * permit creating the serialized form of a Level instance.
    */
    @AtomicSerial
    private static final class LevelData implements Serializable {
        private static final long serialVersionUID = -8176160795706313070L;
        private final String name;
        private final int value;
        private final String resourceBundleName;
        private final String localizedLevelName;

        LevelData(String name, int value, String resourceBundleName) {
            this.name = name;
            this.value = value;
            this.resourceBundleName = resourceBundleName;
            this.localizedLevelName = resourceBundleName == null ? name : null;
        }

	private LevelData(String name,
			  int value,
			  String resourceBundleName,
			  String localizedLevelName)
	{
	    this.name = name;
	    this.value = value;
	    this.resourceBundleName = resourceBundleName;
	    this.localizedLevelName = localizedLevelName;
	}

	public LevelData(GetArg arg) throws IOException{
	    this(arg.get("name", null, String.class),
		 arg.get("value", 0),
		 arg.get("resourceBundleName", null, String.class),
		 arg.get("localizedLevelName", null, String.class)
	    );
	}
    }

    /**
    * Defines an object output stream that allows the data for one class to be
    * interpreted as the data for another class. This class is useful in
    * creating serialization data for a class when access to an appropriate
    * constructor is not available.
    */
    private static final class ClassReplacingObjectOutputStream extends ObjectOutputStream {
        private final ObjectStreamClass from;
        private final ObjectStreamClass to;
        ClassReplacingObjectOutputStream(OutputStream out, Class from, Class to) throws IOException {
            super(out);
            this.from = ObjectStreamClass.lookup(from);
            this.to = ObjectStreamClass.lookup(to);
        }

        protected void writeClassDescriptor(ObjectStreamClass desc) throws IOException {
            if (from.equals(desc)) {
                desc = to;
            }
            super.writeClassDescriptor(desc);
        }
    }

    /**
    * Creates an instance of the Level class. This method works around the
    * fact that there is no public constructor for the Level class by
    * constructing the serialized form for an instance with the specified
    * field values and deserializing it.
    *
    * If deserialization fails, it creates a Level with a numerical name that
    * can be de-serialised by a remote client that doesn't have
    * org.apache.river.logging.Levels bytecode.
    *
    * Local logging code still enjoys the benefit of a meaningful name even
    * when deserialization fails.
    *
    * See River-416 for details, the serial form of Levels was broken in Java 1.6.0_41.
    */
    private static Level createLevel(String name, int value, String resourceBundleName) {
        Level result = null;
        try {
            ByteArrayOutputStream bytes = new ByteArrayOutputStream();
            ObjectOutputStream out = new ClassReplacingObjectOutputStream(bytes, LevelData.class, Level.class);
            out.writeObject(new LevelData(name, value, resourceBundleName));
            out.close();
            ObjectInputStream in = new ObjectInputStream(new ByteArrayInputStream(bytes.toByteArray()));
            result = (Level) in.readObject();
            in.close();
            // If this suceeds, Level.readResolve has added the new Level to its internal List.

        } catch (ClassNotFoundException ex) {
            // Ignore :)
        } catch (IOException e) {
            // Ignore :)
        } finally {
            if (result == null){
                final Level withoutName = Level.parse(Integer.valueOf(value).toString());
                result =  new Level(name, value, resourceBundleName) {
                    Object writeReplace() throws ObjectStreamException {
                        return withoutName;
                    }
                };
            }
            return result;
        }
    }
}