add code

code/Design_Pattern/单例模式/DoubleCheckedLocking.java

@@ -0,0 +1,26 @@
+package Singleton;
+
+public class DoubleCheckedLocking {
+    private static DoubleCheckedLocking instance;
+    public static DoubleCheckedLocking getInstance(){
+        if(instance==null){
+            synchronized (DoubleCheckedLocking.class){
+                if(instance==null){
+                    instance=new DoubleCheckedLocking();
+                }
+            }
+        }
+        return instance;
+    }
+
+    public static void main(String[] args) {
+        for (int i = 0; i < 100; i++) {
+            new Thread(new Runnable() {
+                @Override
+                public void run() {
+                    System.out.println(Thread.currentThread().getName() + ":" + DoubleCheckedLocking.getInstance().hashCode());
+                }
+            }).start();
+        }
+    }
+}

code/Design_Pattern/单例模式/HungrySingleton.java

@@ -0,0 +1,10 @@
+package Singleton;
+
+public class HungrySingleton {
+    private static HungrySingleton instance=new HungrySingleton();
+
+    //加上synchronized来保证线程安全
+    public static  HungrySingleton getInstance(){
+       return instance;
+    }
+}

code/Design_Pattern/单例模式/SafeLazyInitialization.java

@@ -0,0 +1,13 @@
+package Singleton;
+
+public class SafeLazyInitialization {
+    private static SafeLazyInitialization instance;
+
+    //加上synchronized来保证线程安全
+    public static synchronized SafeLazyInitialization getInstance(){
+        if(instance==null){
+            instance=new SafeLazyInitialization();
+        }
+        return instance;
+    }
+}

code/Design_Pattern/单例模式/Static_Class_Singleton.java

@@ -0,0 +1,10 @@
+package Singleton;
+
+public class Static_Class_Singleton {
+    private static class SingletonHolder{
+        private static final Static_Class_Singleton instance=new Static_Class_Singleton();
+    }
+    private static final Static_Class_Singleton getInstance(){
+        return SingletonHolder.instance;
+    }
+}

code/Design_Pattern/单例模式/UnsafeLazyInitialization.java

@@ -0,0 +1,15 @@
+package Singleton;
+
+//1.懒汉模式
+public class UnsafeLazyInitialization {
+    private static UnsafeLazyInitialization instance;
+
+    //加上Synchronized来保证线程安全
+    public static UnsafeLazyInitialization getInstance(){
+        if(instance==null){
+            instance=new UnsafeLazyInitialization();
+        }
+        return instance;
+    }
+
+}

code/Design_Pattern/建造者模式/Computer.java

@@ -0,0 +1,31 @@
+package Design_Pattern.建造者模式;
+
+public class Computer {
+    private String cpu;
+    private String memory;
+    private String disk;
+
+    public String getCpu() {
+        return cpu;
+    }
+
+    public void setCpu(String cpu) {
+        this.cpu = cpu;
+    }
+
+    public String getMemory() {
+        return memory;
+    }
+
+    public void setMemory(String memory) {
+        this.memory = memory;
+    }
+
+    public String getDisk() {
+        return disk;
+    }
+
+    public void setDisk(String disk) {
+        this.disk = disk;
+    }
+}

code/Design_Pattern/建造者模式/ComputerBuilder.java

@@ -0,0 +1,8 @@
+package Design_Pattern.建造者模式;
+
+public interface ComputerBuilder {
+    void builderCpu();
+    void builderMemory();
+    void builderDisk();
+    Computer builderComputer();
+}

code/Design_Pattern/建造者模式/ComputerDirector.java

@@ -0,0 +1,10 @@
+package Design_Pattern.建造者模式;
+
+public class ComputerDirector {
+    public Computer constructComputer(ComputerBuilder computerBuilder){
+        computerBuilder.builderMemory();
+        computerBuilder.builderCpu();
+        computerBuilder.builderDisk();
+        return computerBuilder.builderComputer();
+    }
+}

code/Design_Pattern/建造者模式/ConcreteBuilderTest.java

@@ -0,0 +1,10 @@
+package Design_Pattern.建造者模式;
+
+public class ConcreteBuilderTest {
+    public static void main(String[] args) {
+        ComputerDirector computerDirector=new ComputerDirector();
+        ComputerBuilder computerConcreteBuilder=new CumputerConcreteBuilder();
+        Computer computer=computerDirector.constructComputer(computerConcreteBuilder);
+        System.out.println(computer.getCpu());
+    }
+}

code/Design_Pattern/建造者模式/CumputerConcreteBuilder.java

@@ -0,0 +1,29 @@
+package Design_Pattern.建造者模式;
+
+public class CumputerConcreteBuilder implements ComputerBuilder {
+    Computer computer;
+
+    public CumputerConcreteBuilder() {
+        computer=new Computer();
+    }
+
+    @Override
+    public void builderCpu() {
+        computer.setCpu("8Core");
+    }
+
+    @Override
+    public void builderMemory() {
+        computer.setMemory("16G");
+    }
+
+    @Override
+    public void builderDisk() {
+        computer.setDisk("1TG");
+    }
+
+    @Override
+    public Computer builderComputer() {
+        return computer;
+    }
+}