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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Copyright (C) 2006 The Guava Authors
 *
 * 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 com.google.common.io;

import static com.google.common.base.Preconditions.checkNotNull;

import com.google.common.annotations.GwtIncompatible;
import java.io.Closeable;
import java.io.Flushable;
import java.io.IOException;
import java.io.Writer;
import javax.annotation.CheckForNull;

/**
 * Writer that places all output on an {@link Appendable} target. If the target is {@link Flushable}
 * or {@link Closeable}, flush()es and close()s will also be delegated to the target.
 *
 * @author Alan Green
 * @author Sebastian Kanthak
 * @since 1.0
 */
@GwtIncompatible
@ElementTypesAreNonnullByDefault
class AppendableWriter extends Writer {
  private final Appendable target;
  private boolean closed;

  /**
   * Creates a new writer that appends everything it writes to {@code target}.
   *
   * @param target target to which to append output
   */
  AppendableWriter(Appendable target) {
    this.target = checkNotNull(target);
  }

  /*
   * Abstract methods from Writer
   */

  @Override
  public void write(char[] cbuf, int off, int len) throws IOException {
    checkNotClosed();
    // It turns out that creating a new String is usually as fast, or faster
    // than wrapping cbuf in a light-weight CharSequence.
    target.append(new String(cbuf, off, len));
  }

  /*
   * Override a few functions for performance reasons to avoid creating unnecessary strings.
   */

  @Override
  public void write(int c) throws IOException {
    checkNotClosed();
    target.append((char) c);
  }

  @Override
  public void write(String str) throws IOException {
    checkNotNull(str);
    checkNotClosed();
    target.append(str);
  }

  @Override
  public void write(String str, int off, int len) throws IOException {
    checkNotNull(str);
    checkNotClosed();
    // tricky: append takes start, end pair...
    target.append(str, off, off + len);
  }

  @Override
  public void flush() throws IOException {
    checkNotClosed();
    if (target instanceof Flushable) {
      ((Flushable) target).flush();
    }
  }

  @Override
  public void close() throws IOException {
    this.closed = true;
    if (target instanceof Closeable) {
      ((Closeable) target).close();
    }
  }

  @Override
  public Writer append(char c) throws IOException {
    checkNotClosed();
    target.append(c);
    return this;
  }

  @Override
  public Writer append(@CheckForNull CharSequence charSeq) throws IOException {
    checkNotClosed();
    target.append(charSeq);
    return this;
  }

  @Override
  public Writer append(@CheckForNull CharSequence charSeq, int start, int end) throws IOException {
    checkNotClosed();
    target.append(charSeq, start, end);
    return this;
  }

  private void checkNotClosed() throws IOException {
    if (closed) {
      throw new IOException("Cannot write to a closed writer.");
    }
  }
}