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Commons Net example source code file (ToNetASCIIInputStream.java)

This example Commons Net source code file (ToNetASCIIInputStream.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 - Commons Net tags/keywords

filterinputstream, filterinputstream, io, ioexception, ioexception, override, override, tonetasciiinputstream, tonetasciiinputstream

The Commons Net ToNetASCIIInputStream.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.commons.net.io;

import java.io.FilterInputStream;
import java.io.IOException;
import java.io.InputStream;

/***
 * This class wraps an input stream, replacing all singly occurring
 * <LF> (linefeed) characters with <CR><LF> (carriage return
 * followed by linefeed), which is the NETASCII standard for representing
 * a newline.
 * You would use this class to implement ASCII file transfers requiring
 * conversion to NETASCII.
 * <p>
 * <p>
 ***/

public final class ToNetASCIIInputStream extends FilterInputStream
{
    private static final int __NOTHING_SPECIAL = 0;
    private static final int __LAST_WAS_CR = 1;
    private static final int __LAST_WAS_NL = 2;
    private int __status;

    /***
     * Creates a ToNetASCIIInputStream instance that wraps an existing
     * InputStream.
     * <p>
     * @param input  The InputStream to .
     ***/
    public ToNetASCIIInputStream(InputStream input)
    {
        super(input);
        __status = __NOTHING_SPECIAL;
    }


    /***
     * Reads and returns the next byte in the stream.  If the end of the
     * message has been reached, returns -1.
     * <p>
     * @return The next character in the stream. Returns -1 if the end of the
     *          stream has been reached.
     * @exception IOException If an error occurs while reading the underlying
     *            stream.
     ***/
    @Override
    public int read() throws IOException
    {
        int ch;

        if (__status == __LAST_WAS_NL)
        {
            __status = __NOTHING_SPECIAL;
            return '\n';
        }

        ch = in.read();

        switch (ch)
        {
        case '\r':
            __status = __LAST_WAS_CR;
            return '\r';
        case '\n':
            if (__status != __LAST_WAS_CR)
            {
                __status = __LAST_WAS_NL;
                return '\r';
            }
            //$FALL-THROUGH$
        default:
            __status = __NOTHING_SPECIAL;
            return ch;
        }
        // statement not reached
        //return ch;
    }


    /***
     * Reads the next number of bytes from the stream into an array and
     * returns the number of bytes read.  Returns -1 if the end of the
     * stream has been reached.
     * <p>
     * @param buffer  The byte array in which to store the data.
     * @return The number of bytes read. Returns -1 if the
     *          end of the message has been reached.
     * @exception IOException If an error occurs in reading the underlying
     *            stream.
     ***/
    @Override
    public int read(byte buffer[]) throws IOException
    {
        return read(buffer, 0, buffer.length);
    }


    /***
     * Reads the next number of bytes from the stream into an array and returns
     * the number of bytes read.  Returns -1 if the end of the
     * message has been reached.  The characters are stored in the array
     * starting from the given offset and up to the length specified.
     * <p>
     * @param buffer The byte array in which to store the data.
     * @param offset  The offset into the array at which to start storing data.
     * @param length   The number of bytes to read.
     * @return The number of bytes read. Returns -1 if the
     *          end of the stream has been reached.
     * @exception IOException If an error occurs while reading the underlying
     *            stream.
     ***/
    @Override
    public int read(byte buffer[], int offset, int length) throws IOException
    {
        int ch, off;

        if (length < 1)
            return 0;

        ch = available();

        if (length > ch)
            length = ch;

        // If nothing is available, block to read only one character
        if (length < 1)
            length = 1;

        if ((ch = read()) == -1)
            return -1;

        off = offset;

        do
        {
            buffer[offset++] = (byte)ch;
        }
        while (--length > 0 && (ch = read()) != -1);

        return (offset - off);
    }

    /*** Returns false.  Mark is not supported. ***/
    @Override
    public boolean markSupported()
    {
        return false;
    }

    @Override
    public int available() throws IOException
    {
        int result;

        result = in.available();

        if (__status == __LAST_WAS_NL)
            return (result + 1);

        return result;
    }
}

Other Commons Net examples (source code examples)

Here is a short list of links related to this Commons Net ToNetASCIIInputStream.java source code file:

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