我写了几个名为A.jar,B.jar的简单java应用程序。
现在我想编写一个GUI java程序,以便用户可以按下按钮A执行A.jar,按钮B执行B.jar。
此外,我想在我的GUI程序中输出运行时进程详细信息。
有什么建议吗?
如果我理解正确,您似乎希望在java GUI应用程序内部的单独进程中运行jar。
为此,您可以使用:
// Run a java app in a separate system process
Process proc = Runtime.getRuntime().exec("java -jar A.jar");
// Then retreive the process output
InputStream in = proc.getInputStream();
InputStream err = proc.getErrorStream();
缓冲过程输出总是很好的做法。
.jar不可执行。实例化类或调用任何静态方法。
编辑:创建JAR时添加Main-Class条目。
> p.mf(p.mf的含量)
Main-Class:pk.Test
>Test.java
package pk;
public class Test{
public static void main(String []args){
System.out.println("Hello from Test");
}
}
使用Process类及其方法,
public class Exec
{
public static void main(String []args) throws Exception
{
Process ps=Runtime.getRuntime().exec(new String[]{"java","-jar","A.jar"});
ps.waitFor();
java.io.InputStream is=ps.getInputStream();
byte b[]=new byte[is.available()];
is.read(b,0,b.length);
System.out.println(new String(b));
}
}
希望这可以帮助:
public class JarExecutor {
private BufferedReader error;
private BufferedReader op;
private int exitVal;
public void executeJar(String jarFilePath, List<String> args) throws JarExecutorException {
// Create run arguments for the
final List<String> actualArgs = new ArrayList<String>();
actualArgs.add(0, "java");
actualArgs.add(1, "-jar");
actualArgs.add(2, jarFilePath);
actualArgs.addAll(args);
try {
final Runtime re = Runtime.getRuntime();
//final Process command = re.exec(cmdString, args.toArray(new String[0]));
final Process command = re.exec(actualArgs.toArray(new String[0]));
this.error = new BufferedReader(new InputStreamReader(command.getErrorStream()));
this.op = new BufferedReader(new InputStreamReader(command.getInputStream()));
// Wait for the application to Finish
command.waitFor();
this.exitVal = command.exitValue();
if (this.exitVal != 0) {
throw new IOException("Failed to execure jar, " + this.getExecutionLog());
}
} catch (final IOException | InterruptedException e) {
throw new JarExecutorException(e);
}
}
public String getExecutionLog() {
String error = "";
String line;
try {
while((line = this.error.readLine()) != null) {
error = error + "\n" + line;
}
} catch (final IOException e) {
}
String output = "";
try {
while((line = this.op.readLine()) != null) {
output = output + "\n" + line;
}
} catch (final IOException e) {
}
try {
this.error.close();
this.op.close();
} catch (final IOException e) {
}
return "exitVal: " + this.exitVal + ", error: " + error + ", output: " + output;
}
}
如果jar在你的类路径中,并且你知道它的Main类,你可以只调用主类。以DITA-OT为例:
import org.dita.dost.invoker.CommandLineInvoker;
....
CommandLineInvoker.main('-f', 'html5', '-i', 'samples/sequence.ditamap', '-o', 'test')
请注意,这将使下级jar共享内存空间和jar的类路径,并且可能导致干扰。如果您不希望污染的东西,您还有其他选择,如上所述 - 即:
Runtime.getRuntime.exec(...)
(完全隔离jar,但具有正常的“找到应用程序”,“正确地逃避你的字符串”,“特定于平台的WTF”和“OMG系统线程”运行系统命令的缺陷。以下工作原理通过使用批处理文件启动jar,以防程序作为独立运行:
public static void startExtJarProgram(){
String extJar = Paths.get("C:\\absolute\\path\\to\\batchfile.bat").toString();
ProcessBuilder processBuilder = new ProcessBuilder(extJar);
processBuilder.redirectError(new File(Paths.get("C:\\path\\to\\JavaProcessOutput\\extJar_out_put.txt").toString()));
processBuilder.redirectInput();
try {
final Process process = processBuilder.start();
try {
final int exitStatus = process.waitFor();
if(exitStatus==0){
System.out.println("External Jar Started Successfully.");
System.exit(0); //or whatever suits
}else{
System.out.println("There was an error starting external Jar. Perhaps path issues. Use exit code "+exitStatus+" for details.");
System.out.println("Check also C:\\path\\to\\JavaProcessOutput\\extJar_out_put.txt file for additional details.");
System.exit(1);//whatever
}
} catch (InterruptedException ex) {
System.out.println("InterruptedException: "+ex.getMessage());
}
} catch (IOException ex) {
System.out.println("IOException. Faild to start process. Reason: "+ex.getMessage());
}
System.out.println("Process Terminated.");
System.exit(0);
}
在批处理file.bat中,我们可以说:
@echo off
start /min C:\path\to\jarprogram.jar
如果您是java 1.6,那么还可以执行以下操作:
import javax.tools.JavaCompiler;
import javax.tools.ToolProvider;
public class CompilerExample {
public static void main(String[] args) {
String fileToCompile = "/Users/rupas/VolatileExample.java";
JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
int compilationResult = compiler.run(null, null, null, fileToCompile);
if (compilationResult == 0) {
System.out.println("Compilation is successful");
} else {
System.out.println("Compilation Failed");
}
}
}