This class
describes a process that is running externally to the Java
interpreter. Note that a Process is very different
from a Thread; the Process
class is abstract and cannot be instantiated. Call one of the
Runtime.exec( ) methods to start a process and
return a corresponding Process object.
waitFor( ) blocks until the
process exits. exitValue( ) returns the exit code
of the process. destroy( ) kills the process.
getErrorStream(
) 
 returns
an
InputStream from which you can read any bytes the
process sends to its standard error stream. getInputStream(
) returns an InputStream from which you
can read any bytes the process sends to its standard output stream.
getOutputStream( ) returns an
OutputStream you can use to send bytes to the
standard input stream of the process.
public abstract class Process {
// Public Constructors
     public Process( );  
// Public Instance Methods
     public abstract void destroy( );  
     public abstract int exitValue( );  
     public abstract java.io.InputStream getErrorStream( );  
     public abstract java.io.InputStream getInputStream( );  
     public abstract java.io.OutputStream getOutputStream( );  
     public abstract int waitFor( ) throws InterruptedException;  
}