Package hudson.remoting

Class StandardOutputStream

java.lang.Object

java.io.OutputStream

hudson.remoting.StandardOutputStream

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable

public class StandardOutputStream
extends OutputStream

Hint that indicates that we are using stdout with fd=1 as the stream to write to for the channel.

Using stdin/stdout pair for the communication is very convenient for setting up a remote channel, so Jenkins tends to do that, but even with our using System.setOut(PrintStream) to avoid other parts of the Java code to accidentally corrupt the stream, file descriptor 1 continues to point to the stream we use, so native code in JVM can still accidentally pollute the stream.

Fixing that requires the use of dup and close POSIX API calls, which we can only do after the communication gets established and JNA is brought in via remoting. Having Launcher uses this wrapper class allows us to do that without recreating the stream.

When a channel uses StandardOutputStream to communicate, the convention is to make that object available as a channel property.

Author:

Kohsuke Kawaguchi

Constructor Summary

Constructors

Constructor	Description
StandardOutputStream()

Method Summary

Modifier and Type	Method	Description
void	close()
void	flush()
boolean	isSwapped()
OutputStream	swap(OutputStream another)	Atomically swaps the underlying stream to another stream and returns it.
void	write(byte[] b)
void	write(byte[] b, int off, int len)
void	write(int b)

Methods inherited from class java.io.OutputStream

nullOutputStream

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

StandardOutputStream

public StandardOutputStream()

Method Details

swap

public OutputStream swap(OutputStream another)

Atomically swaps the underlying stream to another stream and returns it.

isSwapped

public boolean isSwapped()

write

public void write(int b)
           throws IOException

Specified by:

write in class OutputStream

Throws:

IOException

write

public void write(@NonNull
 byte[] b)
           throws IOException

Overrides:

write in class OutputStream

Throws:

IOException

write

public void write(@NonNull
 byte[] b,
 int off,
 int len)
           throws IOException

Overrides:

write in class OutputStream

Throws:

IOException

flush

public void flush()
           throws IOException

Specified by:

flush in interface Flushable

Overrides:

flush in class OutputStream

Throws:

IOException

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class OutputStream

Throws:

IOException