ClosedWriter.java
- /*
- * 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 org.apache.commons.io.output;
- import java.io.IOException;
- import java.io.Writer;
- /**
- * Throws an IOException on all attempts to write with {@link #close()} implemented as a noop.
- * <p>
- * Typically uses of this class include testing for corner cases in methods that accept a writer and acting as a
- * sentinel value instead of a {@code null} writer.
- * </p>
- *
- * @since 2.7
- */
- public class ClosedWriter extends Writer {
- /**
- * The singleton instance.
- *
- * @since 2.12.0
- */
- public static final ClosedWriter INSTANCE = new ClosedWriter();
- /**
- * The singleton instance.
- *
- * @deprecated Use {@link #INSTANCE}.
- */
- @Deprecated
- public static final ClosedWriter CLOSED_WRITER = INSTANCE;
- /**
- * Construct a new instance.
- */
- public ClosedWriter() {
- // empty
- }
- @Override
- public void close() throws IOException {
- // noop
- }
- /**
- * Throws an {@link IOException} to indicate that the stream is closed.
- *
- * @throws IOException always thrown
- */
- @Override
- public void flush() throws IOException {
- throw new IOException("flush() failed: stream is closed");
- }
- /**
- * Throws an {@link IOException} to indicate that the writer is closed.
- *
- * @param cbuf ignored
- * @param off ignored
- * @param len ignored
- * @throws IOException always thrown
- */
- @Override
- public void write(final char[] cbuf, final int off, final int len) throws IOException {
- throw new IOException("write(" + new String(cbuf) + ", " + off + ", " + len + ") failed: stream is closed");
- }
- }