更新

src/com/mashibing/jvm/heatload/GetPI.java

@@ -0,0 +1,9 @@
+package com.mashibing.jvm.heatload;
+
+public class GetPI {
+
+    // 本热部署实验中，上面的Darts函数没有用到，请忽略
+    public static void Output() {
+        System.out.println("Output");
+    }
+}  

src/com/mashibing/jvm/heatload/HowswapCL.java

@@ -0,0 +1,112 @@
+package com.mashibing.jvm.heatload;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.lang.reflect.Field;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.util.HashSet;
+
+/*
+ *  实现热部署，自定义ClassLoader，加载的是.class
+ */
+class HowswapCL extends ClassLoader {
+
+    private String basedir; // 需要该类加载器直接加载的类文件的基目录  
+    private HashSet dynaclazns; // 需要由该类加载器直接加载的类名  
+
+    public HowswapCL(String basedir, String[] clazns) {
+        super(null); // 指定父类加载器为 null  
+        this.basedir = basedir;
+        dynaclazns = new HashSet();
+        loadClassByMe(clazns);
+    }
+
+    private void loadClassByMe(String[] clazns) {
+        for (int i = 0; i < clazns.length; i++) {
+            loadDirectly(clazns[i]);
+            dynaclazns.add(clazns[i]);
+        }
+    }
+
+    private Class loadDirectly(String name) {
+        Class cls = null;
+        StringBuffer sb = new StringBuffer(basedir);
+        String classname = name.replace('.', File.separatorChar) + ".class";
+        sb.append(File.separator + classname);
+        File classF = new File(sb.toString());
+        try {
+            cls = instantiateClass(name, new FileInputStream(classF), classF.length());
+        } catch (FileNotFoundException e) {
+            // TODO Auto-generated catch block  
+            e.printStackTrace();
+        }
+        return cls;
+    }
+
+    private Class instantiateClass(String name, InputStream fin, long len) {
+        byte[] raw = new byte[(int) len];
+        try {
+            fin.read(raw);
+            fin.close();
+        } catch (IOException e) {
+            // TODO Auto-generated catch block  
+            e.printStackTrace();
+        }
+
+        return defineClass(name, raw, 0, raw.length);
+    }
+
+    protected Class loadClass(String name, boolean resolve) throws ClassNotFoundException {
+        Class cls = null;
+        cls = findLoadedClass(name);
+        if (!this.dynaclazns.contains(name) && cls == null) {
+            cls = getSystemClassLoader().loadClass(name);
+        }
+        if (cls == null) {
+            throw new ClassNotFoundException(name);
+        }
+        if (resolve) {
+            resolveClass(cls);
+        }
+        return cls;
+    }
+}
+
+/*
+ * 每隔500ms运行一次，不断加载class
+ */
+class Multirun implements Runnable {
+
+    public void run() {
+        try {
+            while (true) {
+                // 每次都创建出一个新的类加载器  
+                // class需要放在自己package名字的文件夹下  
+                String url = "D:\\D\\github\\JVM\\out\\production\\JVM\\";//System.getProperty("user.dir") + "/lib";// "/lib/yerasel/GetPI.jar";
+                HowswapCL cl = new HowswapCL(url, new String[]{"com.mashibing.jvm.heatload.GetPI"});
+                Class cls = cl.loadClass("com.mashibing.jvm.heatload.GetPI");
+                System.out.println(cls.getClassLoader());
+                System.out.println(GetPI.class.getClassLoader());
+                GetPI foo = (GetPI) cls.newInstance();
+                // 被调用函数的参数
+                foo.Output();
+//                Method m = foo.getClass().getMethod("Output", new Class[]{});
+//                m.invoke(foo, new Object[]{});
+                Thread.sleep(500);
+            }
+
+        } catch (Exception ex) {
+            ex.printStackTrace();
+        }
+    }
+}  

src/com/mashibing/jvm/heatload/Test.java

@@ -0,0 +1,26 @@
+package com.mashibing.jvm.heatload;
+
+import java.lang.reflect.Method;
+import java.net.URL;
+import java.net.URLClassLoader;
+
+public class Test {
+
+    public static Method initAddMethod() {
+        try {
+            Method add = URLClassLoader.class.getDeclaredMethod("addURL", new Class[]{URL.class});
+            add.setAccessible(true);
+            return add;
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    public static void main(String[] args) {
+
+        // 热部署测试代码  
+        Thread t;
+        t = new Thread(new Multirun());
+        t.start();
+    }
+}  

src/java/lang/Long.java

@@ -0,0 +1,16 @@
+package java.lang;
+
+/**
+ * @Title: Long
+ * @Description: Long
+ * @Company:www.wrenchdata.com
+ * @author:shenshilong[shilong_shen@163.com]
+ * @date:2019-11-05
+ * @version:V1.0
+ */
+public class Long {
+
+    public static void main(String[] args) {
+        System.out.println(1);
+    }
+}

src/java/lang/Mys.java

@@ -0,0 +1,16 @@
+package java.lang;
+
+/**
+ * @Title: Mys
+ * @Description: Mys
+ * @Company:www.wrenchdata.com
+ * @author:shenshilong[shilong_shen@163.com]
+ * @date:2019-11-05
+ * @version:V1.0
+ */
+public class Mys {
+
+    public static void main(String[] args) {
+        System.out.println(1);
+    }
+}

src/top/fineplug/splitfile/CutDemo.java

@@ -0,0 +1,56 @@
+package top.fineplug.splitfile;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+
+
+public class CutDemo {
+    public static void main(String[] args) {
+        //调用cutFile()函数 传人参数分别为 （原大文件，切割后存放的小文件的路径，切割规定的内存大小）
+        cutFile("D:\\java\\cut\\ForrestGump.avi", "D:\\java\\cuts",1024 * 1024 * 20);
+    }
+
+    private static void cutFile(String src, String endsrc, int num) {
+        FileInputStream fis = null;
+        File file = null;
+        try {
+            fis = new FileInputStream(src);
+            file = new File(src);
+            //创建规定大小的byte数组
+            byte[] b = new byte[num];
+            int len = 0;
+            //name为以后的小文件命名做准备
+            int name = 1;
+            //遍历将大文件读入byte数组中，当byte数组读满后写入对应的小文件中
+            while ((len = fis.read(b)) != -1) {
+                //分别找到原大文件的文件名和文件类型，为下面的小文件命名做准备
+                String name2 = file.getName();
+                int lastIndexOf = name2.lastIndexOf(".");
+                String substring = name2.substring(0, lastIndexOf);
+                String substring2 = name2.substring(lastIndexOf, name2.length());
+                FileOutputStream fos = new FileOutputStream(endsrc + "\\\\"+ substring + "-" + name + substring2);
+                //将byte数组写入对应的小文件中
+                fos.write(b, 0, len);
+                //结束资源
+                fos.close();
+                name++;
+            }
+        } catch (FileNotFoundException e) {
+            e.printStackTrace();
+        } catch (IOException e) {
+            e.printStackTrace();
+        } finally {
+            try {
+                if (fis != null) {
+                    //结束资源
+                    fis.close();
+                }
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+        }
+    }
+}