package com.alter.change.on.demand.jobs;
import java.io.File;
import java.io.IOException;
public class HelloWorld {
public static void main(String args[]){
for(int i = 0; i<5 ; i++){
System.out.println("Helloo");
}
Process process = null;
ProcessBuilder pb = new ProcessBuilder(new String[]{"java" + " " + "com.alter.change.on.demand.jobs.HelloWorld2"});
try {
process = pb.start();
} catch (IOException e) {
e.printStackTrace();
}
try {
process.waitFor();
} catch (InterruptedException e) {
e.printStackTrace();
}
int exitVal = process.exitValue();
System.out.println(exitVal);
}
}
和產生java.io.IOException:不能運行程序 「的Java com.alter.change.on.demand.jobs.HelloWorld2」:錯誤= 2,沒有這樣的文件或目錄
package com.alter.change.on.demand.jobs;
public class HelloWorld2 {
public static void main(String[] args){
System.out.println("Main 2..testing");
}
}
java.io.IOException: Cannot run program "java com.alter.change.on.demand.jobs.HelloWorld2": error=2, No such file or directory
at java.lang.ProcessBuilder.start(ProcessBuilder.java:1048)
at com.alter.change.on.demand.jobs.HelloWorld.main(HelloWorld.java:22)
Caused by: java.io.IOException: error=2, No such file or directory
at java.lang.UNIXProcess.forkAndExec(Native Method)
at java.lang.UNIXProcess.(UNIXProcess.java:248)
at java.lang.ProcessImpl.start(ProcessImpl.java:134)
at java.lang.ProcessBuilder.start(ProcessBuilder.java:1029)
... 1 more
Exception in thread "main" java.lang.NullPointerException
at com.alter.change.on.demand.jobs.HelloWorld.main(HelloWorld.java:28)
您可能正在從錯誤的文件夾編譯它,因爲它位於包中。刪除行'package com.alter.change.on.demand.jobs;' –
錯誤:當包com.alter.change.on.demand.jobs;找不到或加載主類HelloWorld;被刪除 –
這些都在同一個文件中?你如何運行?你需要做'javac HelloWorld.java'然後'java HelloWorld'。 –