java Runtime Process调用可执行文件，子进程阻塞

今天调用mencoder时遇到 Cannot run program " mencoder": CreateProcess error=2, ?????????  查了查，这个可以解决，就拿过来了

我用java调用mencoder实施转码，但是转码过程中出现子进程阻塞，而且还是看了API才知道这个问题的。因为mencoder 的控制台输出信息很多，把缓存区所有的空间占满了，所以程序不能执行后面的程序，mencoder就只能转码28秒的视频，所以需要建立线程及时清空缓存 区。

新建一个类StreamGobble类：

package
 thss.jmencoder;
import
 java.io.BufferedReader;
import
 java.io.IOException;
import
 java.io.InputStream;
import
 java.io.InputStreamReader;
public
 
class
 StreamGobble 
extends
 Thread {
    InputStream is;
    String type;

    StreamGobble(InputStream is, String type) {
        this
.is = is;
        this
.type = type;
    }

    public
 
void
 run() {
        try
 {
            InputStreamReader isr = new
 InputStreamReader(is);
            BufferedReader br = new
 BufferedReader(isr);
            String line = null
;
            while
 ((line = br.readLine()) != 
null
)
                System.out.println(type + ">"
 + line);
        } catch
 (IOException ioe) {
            ioe.printStackTrace();
        }
    }
}

package thss.jmencoder; 
import java.io.BufferedReader; 
import java.io.IOException; 
import java.io.InputStream; 
import java.io.InputStreamReader; 
public class StreamGobble extends Thread { 
    InputStream is; 
    String type; 
    StreamGobble(InputStream is, String type) { 
        this.is = is; 
        this.type = type; 
    } 
    public void run() { 
        try { 
            InputStreamReader isr = new InputStreamReader(is);
            BufferedReader br = new BufferedReader(isr); 
            String line = null; 
            while ((line = br.readLine()) != null) 
                System.out.println(type + ">" + line); 
        } catch (IOException ioe) { 
            ioe.printStackTrace(); 
        } 
    } 
} 

在main函数中调用Runtime/Process执行转码

String line = value.toString();
String[] str = line.split(" "
);
String fOutput = null
;
fOutput = str[3
] + 
".flv"
;
Process process = null
;
try
 {
    Runtime runtime = Runtime.getRuntime();
    process = runtime .exec("mencoder -ofps 30000/1001 -vf harddup"
        + " /user/student/data/"
+str[
0
]
        + " -ss "
+str[
1
]+
" -endpos "
+str[
2
]+
" -sws 2 -of lavf -ovc lavc -lavcopts "
        + "vcodec=flv:vbitrate=500:mbd=2:mv0:trell:v4mv:cbp:last_pred=3 "
        + "-nosound -srate 22050 -o /user/student/data/"
+fOutput);
    new
 StreamGobble(process.getInputStream(), 
"INFO"
).start();
    new
 StreamGobble(process.getErrorStream(), 
"ERROR"
).start();
    int
 status = process.waitFor();
    System.out.println("Process exitValue: "
 + status);
    } catch
 (Throwable t) {
        t.getStackTrace();
    } finally
 {
        if
 (process == 
null
)
            process.destroy();
        process = null
;
    }