| /* |
| * 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. |
| * |
| * |
| ***/ |
| |
| 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. |
| * |
| * @param input The InputStream to wrap. |
| ***/ |
| 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. |
| * |
| * @return The next character in the stream. Returns -1 if the end of the |
| * stream has been reached. |
| * @throws 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. |
| * |
| * @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. |
| * @throws 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. |
| * |
| * @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. |
| * @throws 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; |
| } |
| } |