[Android] [Java] 分享 Process 執行命令列封裝類，androidprocess

[Android] [Java] 分享 Process 執行命令列封裝類，androidprocess

在上一篇文章中提到，利用Java建立進程執行命令列語句建立過多後會出現無法建立進程的問題。

[Android] ProcessBuilder與Runtime.getRuntime().exec分別建立進程的區別

進行多次測試後發現是因為沒有正常退出進程，以及完全讀取掉流資料，和關閉流導致的問題。

在多次最佳化後，建立如下封裝類：

ProcessModel.java

import java.io.BufferedReader;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import java.io.OutputStream;/** * Create By Qiujuer * 2014-07-26 * <p/> * 執行命令列語句靜態方法封裝 */public class ProcessModel {    //分行符號    private static final String BREAK_LINE;    //執行退出命令    private static final byte[] COMMAND_EXIT;    //錯誤緩衝    private static byte[] BUFFER;    /**     * 靜態變數初始化     */    static {        BREAK_LINE = "\n";        COMMAND_EXIT = "\nexit\n".getBytes();        BUFFER = new byte[32];    }    /**     * 執行命令     *     * @param params 命令參數     *               <pre> eg: "/system/bin/ping", "-c", "4", "-s", "100","www.qiujuer.net"</pre>     * @return 執行結果     */    public static String execute(String... params) {        Process process = null;        StringBuilder sbReader = null;        BufferedReader bReader = null;        InputStreamReader isReader = null;        InputStream in = null;        InputStream err = null;        OutputStream out = null;        try {            process = new ProcessBuilder()                    .command(params)                    .start();            out = process.getOutputStream();            in = process.getInputStream();            err = process.getErrorStream();            out.write(COMMAND_EXIT);            out.flush();            process.waitFor();            isReader = new InputStreamReader(in);            bReader = new BufferedReader(isReader);            String s;            if ((s = bReader.readLine()) != null) {                sbReader = new StringBuilder();                sbReader.append(s);                sbReader.append(BREAK_LINE);                while ((s = bReader.readLine()) != null) {                    sbReader.append(s);                    sbReader.append(BREAK_LINE);                }            }            while ((err.read(BUFFER)) > 0) {            }        } catch (IOException e) {            e.printStackTrace();        } catch (Exception e) {            e.printStackTrace();        } finally {            closeAllStream(out, err, in, isReader, bReader);            if (process != null) {                processDestroy(process);                process = null;            }        }        if (sbReader == null)            return null;        else            return sbReader.toString();    }    /**     * 關閉所有流     *     * @param out      輸出資料流     * @param err      錯誤流     * @param in       輸入資料流     * @param isReader 輸入資料流封裝     * @param bReader  輸入資料流封裝     */    private static void closeAllStream(OutputStream out, InputStream err, InputStream in, InputStreamReader isReader, BufferedReader bReader) {        if (out != null)            try {                out.close();            } catch (IOException e) {                e.printStackTrace();            }        if (err != null)            try {                err.close();            } catch (IOException e) {                e.printStackTrace();            }        if (in != null)            try {                in.close();            } catch (IOException e) {                e.printStackTrace();            }        if (isReader != null)            try {                isReader.close();            } catch (IOException e) {                e.printStackTrace();            }        if (bReader != null)            try {                bReader.close();            } catch (IOException e) {                e.printStackTrace();            }    }    /**     * 通過Android底層實現進程關閉     *     * @param process 進程     */    private static void killProcess(Process process) {        int pid = getProcessId(process);        if (pid != 0) {            try {                //android kill process                android.os.Process.killProcess(pid);            } catch (Exception e) {                try {                    process.destroy();                } catch (Exception ex) {                }            }        }    }    /**     * 擷取進程的ID     *     * @param process 進程     * @return     */    private static int getProcessId(Process process) {        String str = process.toString();        try {            int i = str.indexOf("=") + 1;            int j = str.indexOf("]");            str = str.substring(i, j);            return Integer.parseInt(str);        } catch (Exception e) {            return 0;        }    }    /**     * 銷毀進程     *     * @param process 進程     */    private static void processDestroy(Process process) {        if (process != null) {            try {                //判斷是否正常退出                if (process.exitValue() != 0) {                    killProcess(process);                }            } catch (IllegalThreadStateException e) {                killProcess(process);            }        }    }}

在進行批量壓力測試到達125643個線程的時候都沒有出現此問題；特此分享給大家。

怎用java執行命令列

運行cmd.exe 這個程式捕捉process.get InputStream 讀取輸出，捕捉.getOutputStream 發送命令。
 
命令列執行 java 提示找不到主類

cmd命令中不是java hello.class應該是java hello
你試試