Java Virtual machine reads and writes data from other processes--process objects

Using the Exec () method of the runtime object, you can run other programs on the platform that produce a process object that represents a child process that is started by the Java program.

The Process class provides 3 methods for communicating a program to its child processes

InputStream Geterrorstream (): Gets the error stream for the child process.

InputStream Getinputsteeam (): Gets the input stream of the child process.

OutputStream Getoutputstream (): Gets the output stream of the child process.

Example: Reading output information from another process

 PackageCom.chengxuyuanzhiliu;ImportJava.io.BufferedReader;Importjava.io.IOException;ImportJava.io.InputStreamReader; Public classreadfromprocess { Public Static voidMain (string[] args)throwsIOException {Process P= Runtime.getruntime (). EXEC ("Javac"); //try () {}jdk7 new syntax, closes the stream in (), effect type in finally Br.close ()        Try(BufferedReader br =NewBufferedReader (NewInputStreamReader (P.geterrorstream ()))) {String Buff=NULL;  while(Buff = Br.readline ())! =NULL) {System.out.println (buff); }        }    }}

Execution Result:

Similar to the output information example for other processes

Java Virtual machine reads and writes data from other processes--process objects