添加lombok包

Author: enjoyCoding666

javaDemo.iml

@@ -7,6 +7,7 @@
     <content url="file://$MODULE_DIR$">
       <sourceFolder url="file://$MODULE_DIR$/src/main/java" isTestSource="false" />
       <sourceFolder url="file://$MODULE_DIR$/src/test/java" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/main/resource" type="java-resource" />
       <excludeFolder url="file://$MODULE_DIR$/target" />
     </content>
     <orderEntry type="inheritedJdk" />

pom.xml

@@ -16,6 +16,11 @@
         <version>5.1.30</version>
     </dependency>
 
+    <dependency>
+        <groupId>org.projectlombok</groupId>
+        <artifactId>lombok</artifactId>
+        <optional>true</optional>
+    </dependency>
     <!-- 日志文件管理包 -->
     <!-- log start -->
     <dependency>

src/main/java/com/retry/RetryDemo.java

@@ -0,0 +1,75 @@
+package com.retry;
+
+
+import org.apache.log4j.Logger;
+
+import java.util.Random;
+
+/**
+ * 重试
+ *
+ * 服务不稳定的时候，可以重试。
+ *
+ */
+public class RetryDemo {
+    private static final Logger log = Logger.getLogger(RetryDemo.class.getName());
+
+    public static void main(String[] args) throws InterruptedException {
+        retryDoSomething();
+    }
+
+    public static void retryDoSomething() throws InterruptedException {
+        log.info("retryDoSomething start.");
+        //重试次数
+        int maxTimes = 5;
+        //每次重试间隔时间
+        int interval = 500;
+
+        for (int i = 0; i <= maxTimes; i++) {
+            boolean isOk = doSomething();
+            //成功了就停止
+            if (isOk ) {
+                break;
+            }
+            //失败就间隔一段时间后再执行
+            Thread.sleep(interval);
+        }
+        log.info("retryDoSomething end.");
+    }
+
+
+    /**
+     * 执行逻辑，成功就返回 true，报错返回 false
+     *
+     * @return
+     */
+    public static boolean doSomething() {
+        try {
+            //执行逻辑
+            doSth();
+        } catch (Exception e) {
+            log.error("service.doSomething() error.", e);
+            return false;
+        }
+        return true;
+    }
+
+    /**
+     * 执行逻辑的方法
+     *
+     * 以下是示例,可以将示例替换成自己的逻辑
+     *
+     */
+    private static void doSth() {
+        Random random = new Random();
+        //随机产生一个[0-100]之间的随机数，由于是随机，每次执行的结果可能不一样
+        int num = random.nextInt(101);
+        if (num % 5 ==0) {
+            log.info("doSth num:"+ num);
+        } else {
+            //模拟失败，抛异常
+            throw new NumberFormatException();
+        }
+
+    }
+}

src/main/java/test/com/bit/HashTest.java

@@ -0,0 +1,10 @@
+package test.com.bit;
+
+public class HashTest {
+    public static void main(String[] args) {
+        int hash = 19;
+        int i = 15 & hash;
+        System.out.println(hash%15);
+        System.out.println(i);
+    }
+}

src/main/java/test/com/bit/PutValTest.java

@@ -0,0 +1,15 @@
+package test.com.bit;
+
+import com.concurrent.ConcurrentHashMapDemo;
+
+import java.util.concurrent.ConcurrentHashMap;
+
+public class PutValTest {
+    public static void main(String[] args) {
+
+        ConcurrentHashMap<String,String> concurrentHashMap = new ConcurrentHashMap<>();
+        concurrentHashMap.put("abcd", "cccc");
+        System.out.println(concurrentHashMap.get("abcd"));
+
+    }
+}