refactor:增加生成Jdk代理对象工具

src/test/com/mxy/design/proxy/ProxyGeneratorUtils.java

@@ -0,0 +1,33 @@
+package com.mxy.design.proxy;
+
+import org.junit.Test;
+import sun.misc.ProxyGenerator;
+
+import java.io.FileOutputStream;
+import java.io.IOException;
+
+/**
+ * JDK 生成代理类工具
+ */
+public class ProxyGeneratorUtils {
+    /**
+     *  把代理类的字节码写到硬盘上 
+     *  @param path 保存路径 
+     */
+    public static void writeProxyClassToHardDisk(String path) throws IOException {
+        // 第一种方法，这种方式在刚才分析ProxyGenerator时已经知道了
+        // System.getProperties().put("sun.misc.ProxyGenerator.saveGeneratedFiles", true);
+        // 第二种方法
+        // 获取代理类的字节码
+        byte[] classFile = ProxyGenerator.generateProxyClass("$Proxy11", SchoolImpl.class.getInterfaces());
+        FileOutputStream out = null;
+        out = new FileOutputStream(path);
+        out.write(classFile);
+        out.flush();
+    }
+
+    @Test
+    public void write() throws IOException {
+        ProxyGeneratorUtils.writeProxyClassToHardDisk("./$Proxy11.class");
+    }
+}