Java开发常用类和配置文件总结

文章目录

1. UUIDUtil

package com.muluo.crm.utils;
import java.util.UUID;
public class UUIDUtil {
    
    
	public static String getUUID(){
    
    		
		return UUID.randomUUID().toString().replaceAll("-","");		
	}	
}

2. JSON

package com.muluo.crm.utils;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import javax.servlet.http.HttpServletResponse;

import com.fasterxml.jackson.core.JsonGenerationException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;

public class PrintJson {
    
    
	
	//将boolean值解析为json串
	public static void printJsonFlag(HttpServletResponse response,boolean flag){
    
    
		
		Map<String,Boolean> map = new HashMap<String,Boolean>();
		map.put("success",flag);
		
		ObjectMapper om = new ObjectMapper();
		try {
    
    
			//{"success":true}
			String json = om.writeValueAsString(map);
			response.getWriter().print(json);
		} catch (JsonGenerationException e) {
    
    
			e.printStackTrace();
		} catch (JsonMappingException e) {
    
    
			e.printStackTrace();
		} catch (IOException e) {
    
    
			e.printStackTrace();
		}
		
		
		
	}
	
	//将对象解析为json串
	public static void printJsonObj(HttpServletResponse response,Object obj){
    
    
		
		/*
		 * 
		 * Person p
		 * 	id name age
		 * {"id":"?","name":"?","age":?}
		 * 
		 * List<Person> pList
		 * [{"id":"?","name":"?","age":?},{"id":"?","name":"?","age":?},{"id":"?","name":"?","age":?}...]
		 * 
		 * Map
		 * 	key value
		 * {key:value}
		 * 
		 * 
		 */
		
		ObjectMapper om = new ObjectMapper();
		try {
    
    
			String json = om.writeValueAsString(obj);
			response.getWriter().print(json);
		} catch (JsonGenerationException e) {
    
    
			e.printStackTrace();
		} catch (JsonMappingException e) {
    
    
			e.printStackTrace();
		} catch (IOException e) {
    
    
			e.printStackTrace();
		}
				
	}
	
}

3. MD5Util

package com.muluo.crm.utils;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class MD5Util {
	
	public static String getMD5(String password) {
		try {
			// 得到一个信息摘要器
			MessageDigest digest = MessageDigest.getInstance("md5");
			byte[] result = digest.digest(password.getBytes());
			StringBuffer buffer = new StringBuffer();
			// 把每一个byte 做一个与运算 0xff;
			for (byte b : result) {
				// 与运算
				int number = b & 0xff;// 加盐
				String str = Integer.toHexString(number);
				if (str.length() == 1) {
					buffer.append("0");
				}
				buffer.append(str);
			}

			// 标准的md5加密后的结果
			return buffer.toString();
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
			return "";
		}
	}
	
}

4. DateTimeUtil

package com.muluo.crm.utils;

import java.text.SimpleDateFormat;
import java.util.Date;

public class DateTimeUtil {
    
    
	
	public static String getSysTime(){
    
    
		
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
		
		Date date = new Date();
		String dateStr = sdf.format(date);
		
		return dateStr;
		
	}	
}

5. SqlSessionUtil

package com.muluo.crm.utils;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import java.io.IOException;
import java.io.InputStream;

public class SqlSessionUtil {
    
    
	
	private SqlSessionUtil(){
    
    }

	// 基于动态代理
	private static SqlSessionFactory factory;
	
	static{
    
    
		
		String resource = "mybatis-config.xml";
		InputStream inputStream = null;
		try {
    
    
			inputStream = Resources.getResourceAsStream(resource);
		} catch (IOException e) {
    
    
			e.printStackTrace();
		}
		factory = new SqlSessionFactoryBuilder().build(inputStream);
		
	}
	
	private static ThreadLocal<SqlSession> t = new ThreadLocal<SqlSession>();
	
	public static SqlSession getSqlSession(){
    
    
		
		SqlSession session = t.get();
		
		if(session==null){
    
    
			
			session = factory.openSession();
			t.set(session);
		}
		
		return session;
		
	}
	
	public static void myClose(SqlSession session){
    
    
		
		if(session!=null){
    
    
			session.close();
			t.remove();
		}
		
	}
	
	
}

在这里插入图片描述

6. ServiceFactory

package com.muluo.crm.utils;

import org.apache.ibatis.session.SqlSession;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;

public class TransactionInvocationHandler implements InvocationHandler{
    
    
	
	private Object target;
	
	public TransactionInvocationHandler(Object target){
    
    
		
		this.target = target;
		
	}

	public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
    
    
		
		SqlSession session = null;
		
		Object obj = null;
		
		try{
    
    
			session = SqlSessionUtil.getSqlSession();
			
			obj = method.invoke(target, args);
			
			session.commit();
		}catch(Exception e){
    
    
			session.rollback();
			e.printStackTrace();
			
			//处理的是什么异常，继续往上抛什么异常
			throw e.getCause();

		}finally{
    
    
			SqlSessionUtil.myClose(session);
		}
		
		return obj;
	}
	
	public Object getProxy(){
    
    
		
		return Proxy.newProxyInstance(target.getClass().getClassLoader(), target.getClass().getInterfaces(),this);
		
	}
	
}

package com.muluo.crm.utils;

public class ServiceFactory {
    
    
	
	public static Object getService(Object service){
    
    
		
		return new TransactionInvocationHandler(service).getProxy();
		
	}
	
}

在这里插入图片描述

7. log4j.properties

log4j.rootLogger=debug,stdout,file

log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n

log4j.appender.file = org.apache.log4j.FileAppender
log4j.appender.file.File = d\:/logs/ssm.log
log4j.appender.file.Encoding=UTF-8
log4j.appender.file.name = fileLogDemo
log4j.appender.file.Threshold=DEBUG
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%-d{yyyy-MM-dd HH:mm:ss}[ %p ]%m%n
log4j.appender.file.append = true

8. db.properties(c3p0)

jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.jdbcUrl=jdbc\:mysql\://localhost\:3306/luasedu2?characterEncoding=utf8
jdbc.user=root
jdbc.password=root
jdbc.initialPoolSize=10
jdbc.maxPoolSize=100
jdbc.minPoolSize=10
jdbc.acquireIncrement=10

9. pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<groupId>cn.itlaobing</groupId>
	<artifactId>luas</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>war</packaging>

	<!-- 设置统一在编译版本为jdk1.8 -->
	<properties>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
        <maven.compiler.compilerVersion>1.8</maven.compiler.compilerVersion>
    </properties>

	<dependencies>
		<!-- pageHelper分页插件 -->
		<dependency>
			<groupId>com.github.pagehelper</groupId>
			<artifactId>pagehelper</artifactId>
			<version>5.1.11</version>
		</dependency>

		<!-- mybatis逆向工程 -->
		<dependency>
			<groupId>org.mybatis.generator</groupId>
			<artifactId>mybatis-generator-core</artifactId>
			<version>1.4.0</version>
		</dependency>
 
		<!-- spring mvc -->
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-webmvc</artifactId>
			<version>5.2.0.RELEASE</version>
		</dependency>
		
		<!-- 返回json字符串的支持 -->
		<dependency>
			<groupId>com.fasterxml.jackson.core</groupId>
			<artifactId>jackson-databind</artifactId>
			<version>2.10.1</version>
		</dependency>

		<!--JSR303数据校验支持 -->
		<dependency>
			<groupId>org.hibernate</groupId>
			<artifactId>hibernate-validator</artifactId>
			<version>6.1.0.Final</version>
		</dependency>
		
		<!-- Spring-Jdbc -->
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-jdbc</artifactId>
			<version>5.2.0.RELEASE</version>
		</dependency>
		
		<!--Spring-test -->
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-test</artifactId>
			<version>5.2.0.RELEASE</version>
			<scope>test</scope>
		</dependency>
		
		<!-- Spring面向切面编程 -->
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-aop</artifactId>
			<version>5.2.0.RELEASE</version>
		</dependency>
		<dependency>
			<groupId>org.aspectj</groupId>
			<artifactId>aspectjrt</artifactId>
			<version>1.9.5</version>
		</dependency>
		<dependency>
			<groupId>org.aspectj</groupId>
			<artifactId>aspectjweaver</artifactId>
			<version>1.9.5</version>
		</dependency>
		
		<!--MyBatis -->
		<dependency>
			<groupId>org.mybatis</groupId>
			<artifactId>mybatis</artifactId>
			<version>3.5.2</version>
		</dependency>
		
		<!-- MyBatis与Spring的整合包 -->
		<dependency>
			<groupId>org.mybatis</groupId>
			<artifactId>mybatis-spring</artifactId>
			<version>2.0.3</version>
		</dependency>

		<!-- 数据库驱动 -->
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
			<version>5.1.48</version>
		</dependency>
		
		<!-- 数据库连接池 -->
		<dependency>
			<groupId>com.mchange</groupId>
			<artifactId>c3p0</artifactId>
			<version>0.9.5.4</version>
		</dependency>
		
		<!-- JSTL -->
		<dependency>
			<groupId>javax.servlet</groupId>
			<artifactId>jstl</artifactId>
			<version>1.2</version>
		</dependency>
		
		<!-- servlet-api可以来自于tomcat，也可以来自于pom，二者任选其一 -->
		<dependency>
			<groupId>javax.servlet</groupId>
			<artifactId>javax.servlet-api</artifactId>
			<version>3.0.1</version>
			<scope>provided</scope>
		</dependency>
		<!-- jsp-api可以来自于tomcat，也可以来自于pom，二者任选其一 -->
		<dependency>
			<groupId>javax.servlet.jsp</groupId>
			<artifactId>jsp-api</artifactId>
			<version>2.2</version>
			<scope>provided</scope>
		</dependency>

		<!-- 上传文件组件 -->
		<dependency>
			<groupId>commons-fileupload</groupId>
			<artifactId>commons-fileupload</artifactId>
			<version>1.3.1</version>
		</dependency>
        

		<!-- junit -->
		<dependency>
			<groupId>junit</groupId>
			<artifactId>junit</artifactId>
			<version>4.12</version>
			<scope>test</scope>
		</dependency>
	</dependencies>


</project>

Java开发常用类和配置文件总结

文章目录

1. UUIDUtil

2. JSON

3. MD5Util

4. DateTimeUtil

5. SqlSessionUtil

6. ServiceFactory

7. log4j.properties

8. db.properties(c3p0)

9. pom.xml

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