class DynamicReactor://空參構造 public Class<?> dynamicCompile(String srcPath);//輸入一個指定的源文件路徑，若編譯、拷貝成功則返回該類對應的Class類實例 private String changePacketToDic(String packageName);//將一個合法的包名轉換為對應JavaClassPath中的路徑（我是用的是eclipse 所以需要對應地增加bin這一目錄，若使用其他不同編譯器，請參考對應的運行上下文設置進行適當修改） private String getPackage(String srcPath);//由一個合法的java文件路徑嘗試獲得其包名 

import java.io.BufferedReader;import java.io.File;import java.io.FileReader;import java.io.IOException;import java.nio.file.Files;import java.nio.file.Path;import java.nio.file.Paths;import java.nio.file.StandardCopyOption;import java.util.regex.Matcher;import java.util.regex.Pattern;import javax.tools.JavaCompiler;import javax.tools.ToolProvider;/**  * DynamicReactor 一個動態編譯模塊，負責編譯源文件，復制到對應包下及加載類等過程(JDK 1.7)  * @author 三向板磚  * */public class DynamicReactor {	JavaCompiler compiler;	Pattern packagePattern;	static final String regEx = "(?<=package//s).*(?=;)";	public DynamicReactor() 	  {		compiler = ToolProvider.getSystemJavaCompiler();		packagePattern = Pattern.compile(regEx);	}	/**    * 動態編譯給定源文件    * @param srcPath 源文件路徑    * @return Class    *   <br>若成功返回對應類的Class實例    *   <br>若失敗返回null    * */	public Class<?> dynamicCompile(String srcPath) 	  {		Class<?> result = null;		//獲得給定路徑源文件的 		String packName = getPackage(srcPath);		if(packName == null) 		    {			System.out.println("DynamicRector:Load packageName Error!");			return null;		}		//調用compiler編譯指定源文件 		int res = compiler.run(null, null, null,srcPath);		if(res != 0) 		    {			System.out.println("DynamicRector:Compile Java Source Error!");			return null;		}		//獲得包名對應的路徑，若路徑不存在則創建，若指定class文件存在則覆蓋 		String packageDst = changePacketToDic(packName);		File dstDir = new File(packageDst);		if(!dstDir.exists()) 		    {			dstDir.mkdirs();		}		Path pathFrom = Paths.get(srcPath.split("//.java")[0] + ".class");		Path pathTo = Paths.get(packageDst,pathFrom.getFileName().toString());		try {			Files.move(pathFrom, pathTo, StandardCopyOption.REPLACE_EXISTING);		}		catch (IOException e) {			System.out.println("DynamicRector:Move File Fail!");			e.printStackTrace();		}		try {			result = Class.forName(packName+"."+pathFrom.getFileName().toString().split("//.class")[0]);		}		catch (ClassNotFoundException e) {			System.out.println("DynamicRector:Class Not found in Final!");		}		return result;	}	//該方法將一個合法包名轉化為對應路徑 	private String changePacketToDic(String packageName) 	  {		String[] dirs = packageName.split("//.");		String res = ".//bin";		for (int i = 0;i < dirs.length;i++) 		    {			res += "//"+dirs[i];		}		return res;	}	//該方法從給定的路徑源文件中獲得包名 	private String getPackage(String srcPath) 	  {		String result = null;		BufferedReader br;		try {			br = new BufferedReader(new FileReader(srcPath));			String data = br.readLine();			while(data != null) 			      {				if(data.indexOf("package") != -1) 				        {					Matcher m = packagePattern.matcher(data);					if(m.find()) 					          {						result = m.group();					}					break;				}				data = br.readLine();			}			br.close();		}		catch (IOException e) {			System.out.println("DynamicRector:Error in open file "+srcPath);		}		return result;	}}