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我已經花了3天，沒有太多的運氣在谷歌上如何從Java內部運行grep進程。從Java程序運行grep
我有下面的代碼來運行一個grep進程，但是，我只得到響應的第一行。
package com.example.parser;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class Main {
public static void main(String[] args) {
try {
Process process = new ProcessBuilder("grep", "-rni", "\"public static void main(\"", "/home/user/dev/java/").start();
BufferedReader br = new BufferedReader(new InputStreamReader(process.getInputStream()));
String line = "";
while((line = br.readLine()) != null) {
System.out.println(line);
}
System.out.println("Exit Code: " + process.exitValue());
} catch (IOException e) {
e.printStackTrace();
}
}
}
我只得到如下回應：
Binary file /home/user/dev/java/Parser/parser/bin/com/example/parser/Main.class matches
Exit Code: 0
當我應該得到如下回應：
Binary file /home/user/dev/java/Parser/parser/com/example/parser/Main.class matches
/home/user/dev/java/Parser/parser/src/com/example/parser/Main.java:10: public static void main(String[] args) {
/home/user/dev/java/Parser/parser/src/com/example/parser/Main.java:12: Process process = new ProcessBuilder("grep", "-rni", "\"public static void main(\"", "/home/user/dev/java/Parser/parser").start();
Exit Code: 0
我很奇怪，爲什麼我只得到輸出爲首次發現？是grep分叉幾個進程來運行搜索，我只得到第一個處理？
我也試圖從一個線程運行的進程：
包com.example.parser;
public class Main {
public static void main(String[] args) {
try {
Analyzer analyzer = new Analyzer();
analyzer.start();
analyzer.join();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
package com.example.parser;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class Analyzer extends Thread {
public Analyzer() {
}
@Override
public void run() {
try {
Process process = new ProcessBuilder("grep", "-rni", "\"public static void main(\"", "/home/user/dev/java/Parser/parser").start();
process.waitFor();
BufferedReader br = new BufferedReader(new InputStreamReader(process.getInputStream()));
String line = "";
while((line = br.readLine()) != null) {
System.out.println(line);
}
System.out.println("Exit Code: " + process.exitValue());
} catch (IOException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
還有以下幾點：
package com.example.parser;
import java.io.IOException;
public class Main {
public static void main(String[] args) {
try {
Process process = new ProcessBuilder("grep", "-rni", "\"public static void main(\"", "/home/user/dev/java/Parser/parser").start();
process.waitFor();
Analyzer analyzer_is = new Analyzer(process.getInputStream());
Analyzer analyzer_es = new Analyzer(process.getErrorStream());
analyzer_is.start();
analyzer_es.start();
analyzer_is.join();
analyzer_es.join();
System.out.println("Exit Code: " + process.exitValue());
} catch (IOException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
package com.example.parser;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
public class Analyzer extends Thread {
InputStream is = null;
public Analyzer(InputStream is) {
this.is = is;
}
@Override
public void run() {
try {
BufferedReader br = new BufferedReader(new InputStreamReader(this.is));
String line = "";
while((line = br.readLine()) != null) {
System.out.println(line);
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
由於建議通過以下文章：http://www.javaworld.com/jw-12-2000/jw-1229-traps.html
是否有除了學習如何使用'ProcessBuilder'的終極目標？ –
@Dave：不確定你的問題是什麼意思？ – ossys
沒錯，如果你想用Java代碼做一些事情，尤其是像名字所暗示的「解析」的東西，不知道你爲什麼要這樣做。換句話說，如果你的最終目標是某種形式的Java程序操作，你爲什麼要這樣做？ –