Streams.java Source code

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Here is the source code for Streams.java

Source

/*
 * 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.
 */

import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Reader;
import java.io.Writer;
import java.io.InputStreamReader;

/**
 * Utility functions related to Streams.
 *
 * @author <a href="mailto:taylor@apache.org">David Sean Taylor</a>
 * @version $Id: Streams.java 516448 2007-03-09 16:25:47Z ate $
 */
public class Streams {
    static final int BLOCK_SIZE = 4096;

    public static void drain(InputStream r, OutputStream w) throws IOException {
        byte[] bytes = new byte[BLOCK_SIZE];
        try {
            int length = r.read(bytes);
            while (length != -1) {
                if (length != 0) {
                    w.write(bytes, 0, length);
                }
                length = r.read(bytes);
            }
        } finally {
            bytes = null;
        }

    }

    public static void drain(Reader r, Writer w) throws IOException {
        char[] bytes = new char[BLOCK_SIZE];
        try {
            int length = r.read(bytes);
            while (length != -1) {
                if (length != 0) {
                    w.write(bytes, 0, length);
                }
                length = r.read(bytes);
            }
        } finally {
            bytes = null;
        }

    }

    public static void drain(Reader r, OutputStream os) throws IOException {
        Writer w = new OutputStreamWriter(os);
        drain(r, w);
        w.flush();
    }

    public static void drain(InputStream is, Writer w) throws IOException {
        Reader r = new InputStreamReader(is);
        drain(r, w);
        w.flush();
    }

    public static byte[] drain(InputStream r) throws IOException {
        ByteArrayOutputStream bytes = new ByteArrayOutputStream();
        drain(r, bytes);
        return bytes.toByteArray();
    }

    public static String getAsString(InputStream is) {
        int c = 0;
        char lineBuffer[] = new char[128], buf[] = lineBuffer;
        int room = buf.length, offset = 0;
        try {
            loop: while (true) {
                // read chars into a buffer which grows as needed
                switch (c = is.read()) {
                case -1:
                    break loop;

                default:
                    if (--room < 0) {
                        buf = new char[offset + 128];
                        room = buf.length - offset - 1;
                        System.arraycopy(lineBuffer, 0, buf, 0, offset);
                        lineBuffer = buf;
                    }
                    buf[offset++] = (char) c;
                    break;
                }
            }
        } catch (IOException ioe) {
            ioe.printStackTrace();
        }
        if ((c == -1) && (offset == 0)) {
            return null;
        }
        return String.copyValueOf(buf, 0, offset);
    }

}