随笔分类 - java
摘要:hashMap的底层数据结构是哈希表,哈希表又由数组加链表构成,在执行put操作时,hashMap会根据key进行哈希函数运算,插入数组中,如果哈希冲突那么由于hashMap采用的是链地址法,会对冲突的键值对形成链表,如果哈希值相同并且关键字也相同,那么会直接修改原来的value值,在java8之后
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摘要:点击查看代码 package it_09; import java.util.function.Supplier; public class Demo5 { public static void main(String[] args) { int[] array ={2,6,9,5,3}; int
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摘要:接口add 点击查看代码 package it_09; public interface Add { public int add(int a,int b); } main 点击查看代码 public class Demo1 { public static void main(String[] ar
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摘要:
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摘要:点击查看代码 package it_08; public class Demo6 { public static void main(String[] args) { // MyRunnable myRunnable = new MyRunnable(); // Thread t1 = new Th
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摘要:cilent 点击查看代码 package it_08; import java.io.*; import java.net.Socket; //客户端 public class Demo3 { public static void main(String[] args) throws IOExce
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摘要:cilent 点击查看代码 package it_08; import java.io.*; import java.net.Socket; //客户端 public class Demo3 { public static void main(String[] args) throws IOExce
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摘要:cilent 点击查看代码 package it_08; import java.io.*; import java.net.Socket; //客户端 public class Demo3 { public static void main(String[] args) throws IOExce
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摘要:客户端先写数据 点击查看代码 package it_08; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.net.InetAddress; import
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摘要:发送数据 点击查看代码 package it_07; import java.io.IOException; import java.net.*; public class Demo3 { public static void main(String[] args) throws IOExcepti
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摘要:box 点击查看代码 package it_07; import java.util.concurrent.locks.Lock; import java.util.concurrent.locks.ReentrantLock; public class Box { private int milk
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摘要:点击查看代码 package it_06; import java.util.concurrent.locks.Lock; import java.util.concurrent.locks.ReentrantLock; public class SellTicket implements Runn
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摘要:点击查看代码 package it_06; import java.util.*; public class Demo11 { public static void main(String[] args) { StringBuffer sb =new StringBuffer(); Vector<S
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摘要:多线程问题必须满足这三个条件才会触发 1.多线程 2.共享数据 3.有多条语句操作共享数据 用同步代码块的弊端,每个线程都要判断一下是否上了锁,耗费资源 SellTicket类 点击查看代码 package it_06; public class SellTicket implements Runn
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摘要:MyRunnable类 点击查看代码 package it_06; public class MyRunnable implements Runnable{ @Override public void run() { for(int i=0;i<100;i++){ System.out.printl
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摘要:join 点击查看代码 package it_06; public class Demo7 { public static void main(String[] args) { MyThread t1 =new MyThread("A"); MyThread t2 =new MyThread("B"
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摘要:MyThread类必须重写run 方法 点击查看代码 package it_06; public class MyThread extends Thread { MyThread(){} MyThread(String name){ super(name); } @Override public v
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摘要:student 点击查看代码 package it_01; import java.io.Serializable; import java.util.Objects; public class Student implements Serializable { private static fin
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摘要:package it_05; import java.io.*; public class Demo8 { public static void main(String[] args) throws Exception { File srcFolder =new File("D:\\game");
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摘要:package it_05; import java.io.*; public class Demo7 { public static void main(String[] args) throws Exception { File srcFolder = new File("D:\\game\\J
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