Apache CXF example source code file (IOUtils.java)

This example Apache CXF source code file (IOUtils.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Apache CXF tags/keywords

bytearrayoutputstream, default_buffer_size, default_buffer_size, inputstream, inputstream, io, ioexception, ioexception, loadingbytearrayoutputstream, outputstream, reader, runtimeexception, string, string, stringbuilder

The Apache CXF IOUtils.java source code

/**
 * 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.cxf.helpers;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.Reader;
import java.io.UnsupportedEncodingException;
import java.io.Writer;
import java.nio.charset.Charset;

public final class IOUtils {
    public static final Charset UTF8_CHARSET = Charset.forName("utf-8");
    private static final int DEFAULT_BUFFER_SIZE = 1024 * 4;

    private IOUtils() {

    }
    
    /**
     * Use this function instead of new String(byte[], String) to avoid surprises from 
     * non-standard default encodings.
     * @param bytes
     * @param charsetName
     * @return
     */
    public static String newStringFromBytes(byte[] bytes, String charsetName) {
        try {
            return new String(bytes, charsetName);
        } catch (UnsupportedEncodingException e) {
            throw 
                new RuntimeException("Impossible failure: Charset.forName(\""
                                     + charsetName + "\") returns invalid name.");

        }
    }
    
    
    /**
     * Use this function instead of new String(byte[]) to avoid surprises from non-standard default encodings.
     * @param bytes
     * @return
     */
    public static String newStringFromBytes(byte[] bytes) {
        return newStringFromBytes(bytes, UTF8_CHARSET.name());        
    }
    
    /**
     * Use this function instead of new String(byte[], int, int, String) 
     * to avoid surprises from non-standard default encodings.
     * @param bytes
     * @param charsetName
     * @param start
     * @param length
     * @return
     */
    public static String newStringFromBytes(byte[] bytes, String charsetName, int start, int length) {
        try {
            return new String(bytes, start, length, charsetName);
        } catch (UnsupportedEncodingException e) {
            throw 
                new RuntimeException("Impossible failure: Charset.forName(\""
                                     + charsetName + "\") returns invalid name.");

        }
    }

    /**
     * Use this function instead of new String(byte[], int, int) 
     * to avoid surprises from non-standard default encodings.
     * @param bytes
     * @param start
     * @param length
     * @return
     */
    public static String newStringFromBytes(byte[] bytes, int start, int length) {
        return newStringFromBytes(bytes, UTF8_CHARSET.name(), start, length);
    }

    public static int copy(final InputStream input, final OutputStream output)
        throws IOException {
        return copy(input, output, DEFAULT_BUFFER_SIZE);
    }

    public static int copyAndCloseInput(final InputStream input,
            final OutputStream output) throws IOException {
        try {
            return copy(input, output, DEFAULT_BUFFER_SIZE);
        } finally {
            input.close();
        }
    }

    public static int copyAndCloseInput(final InputStream input,
            final OutputStream output, int bufferSize) throws IOException {
        try {
            return copy(input, output, bufferSize);
        } finally {
            input.close();
        }
    }

    public static int copy(final InputStream input, final OutputStream output,
            int bufferSize) throws IOException {
        int avail = input.available();
        if (avail > 262144) {
            avail = 262144;
        }
        if (avail > bufferSize) {
            bufferSize = avail;
        }
        final byte[] buffer = new byte[bufferSize];
        int n = 0;
        n = input.read(buffer);
        int total = 0;
        while (-1 != n) {
            if (n == 0) {
                throw new IOException("0 bytes read in violation of InputStream.read(byte[])");
            }
            output.write(buffer, 0, n);
            total += n;
            n = input.read(buffer);
        }
        return total;
    }

    public static void copy(final Reader input, final Writer output,
            final int bufferSize) throws IOException {
        final char[] buffer = new char[bufferSize];
        int n = 0;
        n = input.read(buffer);
        while (-1 != n) {
            if (n == 0) {
                throw new IOException("0 bytes read in violation of InputStream.read(byte[])");
            }
            output.write(buffer, 0, n);
            n = input.read(buffer);
        }
    }

    public static String toString(final InputStream input) throws IOException {
        return toString(input, DEFAULT_BUFFER_SIZE);
    }
    public static String toString(final InputStream input, String charset) throws IOException {
        return toString(input, DEFAULT_BUFFER_SIZE, charset);
    }
    public static String toString(final InputStream input, int bufferSize)
        throws IOException {
        return toString(input, bufferSize, null);
    }
    public static String toString(final InputStream input, int bufferSize, String charset)
        throws IOException {

        
        int avail = input.available();
        if (avail > bufferSize) {
            bufferSize = avail;
        }
        Reader reader = charset == null ? new InputStreamReader(input, UTF8_CHARSET) 
            : new InputStreamReader(input, charset);
        return toString(reader, bufferSize);
    }

    public static String toString(final Reader input) throws IOException {
        return toString(input, DEFAULT_BUFFER_SIZE);
    }
    public static String toString(final Reader input, int bufSize) throws IOException {

        StringBuilder buf = new StringBuilder();
        final char[] buffer = new char[bufSize];
        int n = 0;
        n = input.read(buffer);
        while (-1 != n) {
            if (n == 0) {
                throw new IOException("0 bytes read in violation of InputStream.read(byte[])");
            }
            buf.append(new String(buffer, 0, n));
            n = input.read(buffer);
        }
        input.close();
        return buf.toString();
    }

    public static String readStringFromStream(InputStream in)
        throws IOException {

        StringBuilder sb = new StringBuilder(1024);

        for (int i = in.read(); i != -1; i = in.read()) {
            sb.append((char) i);
        }

        in.close();

        return sb.toString();
    }

    /**
     * Load the InputStream into memory and return a ByteArrayInputStream that
     * represents it. Closes the in stream.
     * 
     * @param in
     * @return
     * @throws IOException
     */
    public static ByteArrayInputStream loadIntoBAIS(InputStream in)
        throws IOException {
        int i = in.available();
        if (i < DEFAULT_BUFFER_SIZE) {
            i = DEFAULT_BUFFER_SIZE;
        }
        LoadingByteArrayOutputStream bout = new LoadingByteArrayOutputStream(i);
        copy(in, bout);
        in.close();
        return bout.createInputStream();
    }

    public static byte[] readBytesFromStream(InputStream in) throws IOException {
        int i = in.available();
        if (i < DEFAULT_BUFFER_SIZE) {
            i = DEFAULT_BUFFER_SIZE;
        }
        ByteArrayOutputStream bos = new ByteArrayOutputStream(i);
        copy(in, bos);
        in.close();
        return bos.toByteArray();
    }
}