命令行运行Java
? 很久没在命令行运行Java了，今天突然要运行一个觉得是在是生疏，虽然之前已有同样的经过，可惜没记录下来，吃一堑长一智，这次必须得记录下来了。
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?? 我首先遇到的第一个问题是编码问题，因为我是在eclipse上写好的一个测试类ApacheStatusStatistic.java，并且能在eclipse上能正确运行。但是当我把这个文件拷贝文件 E:\test目录下，并在命令行执行时，其报“需要为 class,interface或enum....”错误，详情如下：
经多翻查找，终于知道其为编码问题，原来在ecplise环境中的编码是UTF-8,改为ANSI就解决了。
? 遇到的第二个问题是编译运行的问题。我的类如下：
package apache;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;import java.net.MalformedURLException;import java.util.HashMap;import java.util.Map;public class ApacheStatusStatistic {/** * @param args */public static void main(String[] args) {try {java.net.URL url = new java.net.URL("http://www.apache.org/server-status?auto");BufferedReader in = new BufferedReader(new InputStreamReader(url.openStream()));String open = "Open";String waiting = "Waiting";String readingRequest = "Reading request";String sendingReply = "Sending reply";String keepingAlive = "Keeping alive";String dnsLookup = "DNS lookup";String logging = "Logging";// 额外的String startingUp = "Starting up";String closingConnection = "Closing connection";String gracefullyFinishing = "Gracefully finishing";String idleCleanupofWorker = "Idle cleanup of worker";Map<String, Integer> data = new HashMap<String, Integer>();data.put(open, 0);data.put(waiting, 0);data.put(readingRequest, 0);data.put(sendingReply, 0);data.put(keepingAlive, 0);data.put(dnsLookup, 0);data.put(logging, 0);// 额外的data.put(startingUp, 0);data.put(closingConnection, 0);data.put(gracefullyFinishing, 0);data.put(idleCleanupofWorker, 0);String str;System.out.println("基本统计数据如下:");while ((str = in.readLine()) != null) {if (str.startsWith("Scoreboard:")) {String scoreboard = str.substring(11);// System.out.println(scoreboard);for (int i = 0; i < scoreboard.length(); i++) {char c = scoreboard.charAt(i);switch (c) {case '_':data.put(waiting, data.get(waiting) + 1);break;case 'S':data.put(startingUp, data.get(startingUp) + 1);break;case 'R':data.put(readingRequest, data.get(readingRequest) + 1);break;case 'W':data.put(sendingReply, data.get(sendingReply) + 1);break;case 'K':data.put(keepingAlive, data.get(keepingAlive) + 1);break;case 'D':data.put(dnsLookup, data.get(dnsLookup) + 1);break;case 'C':data.put(closingConnection, data.get(closingConnection) + 1);break;case 'L':data.put(logging, data.get(logging) + 1);break;case 'G':data.put(gracefullyFinishing, data.get(gracefullyFinishing) + 1);break;case 'I':data.put(idleCleanupofWorker, data.get(idleCleanupofWorker) + 1);break;/** Open slot with no current process */case '.':data.put(open, data.get(open) + 1);break;}}} else {System.out.println(str);}}System.out.println("状态统计数据如下:");System.out.println(open + ":" + data.get(open));System.out.println(waiting + ":" + data.get(waiting));System.out.println(readingRequest + ":" + data.get(readingRequest));System.out.println(sendingReply + ":" + data.get(sendingReply));System.out.println(keepingAlive + ":" + data.get(keepingAlive));System.out.println(dnsLookup + ":" + data.get(dnsLookup));System.out.println(logging + ":" + data.get(logging));/** 额外的*/System.out.println(startingUp + ":" + data.get(startingUp));System.out.println(closingConnection + ":" + data.get(closingConnection));System.out.println(gracefullyFinishing + ":" + data.get(gracefullyFinishing));System.out.println(idleCleanupofWorker + ":" + data.get(idleCleanupofWorker));in.close();} catch (MalformedURLException e) {} catch (IOException ee) {}}}?? 我编译并运行，但结果却是“no class def found error”，详情如下：
?后来经过调查时，运行编译好的文件时，必须进入其所在的目录如下图所示：
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但我运行时却报：Exception in thread "main" java.lang.NoClassDefFoundError: ApacheStatusStatistic (wrong name: apache/ApacheStatusStatistic)，详情如下：
经过调查因为包的问题，如果Java类有包名，你必须建相应的包文件夹并把文件编译或拷贝到到相应的文件夹下，如这里
我得在E:\test下创建文件夹apache并把ApacheStatusStatistic.class拷贝到这个文件夹下。并且必须在命令行指定包名，执行如下才成功运行：
终于搞定，铭刻于心呀