javax.servlet.ServletInputStream Maven / Gradle / Ivy
/*
* JBoss, Home of Professional Open Source.
* Copyright 2007, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package javax.servlet;
import java.io.InputStream;
import java.io.IOException;
/**
* Provides an input stream for reading binary data from a client request,
* including an efficient readLine method for reading data one
* line at a time. With some protocols, such as HTTP POST and PUT, a
* ServletInputStream object can be used to read data sent from
* the client.
*
* A ServletInputStream object is normally retrieved via the
* {@link ServletRequest#getInputStream} method.
*
* This is an abstract class that a servlet container implements. Subclasses of
* this class must implement the java.io.InputStream.read()
* method.
*
* @author Various
* @see ServletRequest
*/
public abstract class ServletInputStream extends InputStream
{
/**
* Does nothing, because this is an abstract class.
*/
protected ServletInputStream()
{
}
/**
* Reads the input stream, one line at a time. Starting at an offset, reads
* bytes into an array, until it reads a certain number of bytes or reaches a
* newline character, which it reads into the array as well.
*
* This method returns -1 if it reaches the end of the input stream before
* reading the maximum number of bytes.
*
* @param b
* an array of bytes into which data is read
* @param off
* an integer specifying the character at which this method begins
* reading
* @param len
* an integer specifying the maximum number of bytes to read
* @return an integer specifying the actual number of bytes read, or -1 if
* the end of the stream is reached
* @exception IOException
* if an input or output exception has occurred
*/
public int readLine(byte[] b, int off, int len) throws IOException
{
if (len <= 0)
{
return 0;
}
int count = 0, c;
while ((c = read()) != -1)
{
b[off++] = (byte) c;
count++;
if (c == '\n' || count == len)
{
break;
}
}
return count > 0 ? count : -1;
}
}