1.依赖 pom.xml
<dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-aop</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-configuration-processor</artifactId> <optional>true</optional> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency> </dependencies>
2Spring Boot 的配置文件
1. spring boot有两种格式配置文件：1.application.properties 传统的key/value配置
2.application.yml 分支配置
不同环境不同配置的切换：
properties-dev是开发环境
properties-prod是生产环境
开发环境可以在application.peoperties中加入以下配置：
生产环境：
2.项目相关配置
server.port=8081
切换端口，默认端口是8080
server.servlet.path=/employee
切换根路径
3.spring boot配置加载类
@SpringBootApplication
public class EmployeeApplication {
public static void main(String[] args) {
SpringApplication.run(EmployeeApplication.class, args);
}
}
默认加载了application.properties/application.yml中的配置
如果pom.xml中有jpa和mysql的依赖，那么会加载默认的数据源，如果在application.propeties没有配置则会报错；
如果不用配置源：则可以在主配置类上添加
@EnableAutoConfiguration
4.@value注解的使用
在配置文件中定义：cupSize=F
在类中可以通过@Value取得
@Value("{cupSize}")
private String cupSize;
并且不用考虑常用类型转换：
age=10
@Value("{age}")
private Integer age;
5.自动把配置文件的value注入到实体类
package com.victor.employee.pojo; import org.springframework.boot.context.properties.ConfigurationProperties; @component @ConfigurationProperties(prefix = "gril") public class Gril { private String name; private Integer age; public String getName() { return name; } public void setName(String name) { this.name = name; } public Integer getAge() { return age; } public void setAge(Integer age) { this.age = age; } }
@ConfigurationProperties(prefix = "gril")
该注解把配置文件中girl的属性注入到实体中
@Component
实例化实体bean
application。properties：
gril.name=yin gril.age=18
使用@autowired加载使用
@Autowired
private Gril gril;
6.Controller中注解
package com.victor.employee.Controller;
import com.victor.employee.pojo.Employee;
import com.victor.employee.service.EmployeeService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
import javax.validation.Valid;
import java.util.List;
@RestController
public class EmployeeController {
@Autowired
private Employee employee;
@Autowired
private EmployeeService employeeService;
@RequestMapping(value = "/hello",method = RequestMethod.GET)
public String hello(){
return "hello world"+employee.getName();
}
@RequestMapping(value = "/findall",method = RequestMethod.GET)
public List<Employee> findAll(){
return employeeService.findAll();
}
@RequestMapping(value = "/insert",method = RequestMethod.POST)
public Employee insert(@Valid Employee employee, BindingResult result) {
if (result.hasErrors()) {
System.out.print(result.getFieldError().getDefaultMessage());
return null;
}
return employeeService.save(employee);
}
}
@RestController是俩个注解的合并
@Controller
@ResponseBody
@RequesMapping定义访问路径；用在类上为二级目录；方法上为方法路径
参数:
value:指定路径
method:指定那种方法可以访问post还是get等
获取路径中的参数@PathVariable
@RequestMapping(value = "/hello/{id}",method = RequestMethod.GET)
public String hello(@PathVariable("id")Integer id){
return "hello world"+employee.getName()+id;
}
获取localhost:8080/hello?id=10这样的的参数并制定默认值@RequestParam
public String hello(@RequestParam(value="id" ,required = false,defaultValue ="1") Integer id){
return "hello world"+employee.getName()+id;
}
7.数据库的操作
配置数据源
spring.datasource.url=jdbc:mysql://localhost/dbgirl spring.datasource.username=root spring.datasource.password=luohao310545 spring.datasource.driver-class-name=com.mysql.jdbc.Driver spring.jpa.hibernate.ddl-auto=update spring.jpa.show-sql=true
建立实体类Employee
package com.victor.employee.pojo;
import org.springframework.stereotype.Component;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.validation.constraints.Min;
/**
* 实体类
*/
@Entity//声明该类是一个实体
@Component//自动生成bean
public class Employee {
@Id//主键
@GeneratedValue//自动生成
private Integer id;
private String name;
@Min(value=18,message = "未成年禁止")//插入数据库中对年龄的限制
private Integer age;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public Employee() {
}
@Override
public String toString() {
return "Employee{" +
"id=" + id +
", name=‘" + name + ‘\‘‘ +
", age=" + age +
‘}‘;
}
}
建立dao接口并继承JpaRepository接口
EmployeeDao
package com.victor.employee.dao;
import com.victor.employee.pojo.Employee;
import org.springframework.data.jpa.repository.JpaRepository;
public interface EmployeeDao extends JpaRepository<Employee,Integer> {
}
建立service接口与实现
EmployeeService ...
EmployeeServiceImpl
package com.victor.employee.service.Impl;
import com.victor.employee.common.Const;
import com.victor.employee.common.RestResult;
import com.victor.employee.dao.EmployeeDao;
import com.victor.employee.exception.LocalException;
import com.victor.employee.pojo.Employee;
import com.victor.employee.service.EmployeeService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import javax.transaction.Transactional;
import java.util.List;
@Service("employeeService")
@Transactional
public class EmployeeServiceImpl implements EmployeeService{
@Autowired
private EmployeeDao employeeDao;
public List<Employee> findAll(){
return employeeDao.findAll();
}
public Employee save(Employee employee){
return employeeDao.save(employee);
}
public RestResult<String> getEmployee(Integer id)throws Exception{
Employee employee=employeeDao.getOne(id);
Integer age=employee.getAge();
if(age<10){
throw new LocalException(Const.ExceptionCode.YEARSUP.getCode(),Const.ExceptionCode.YEARSUP.getMsg());
}
else if(age<15&&age>10){
throw new LocalException(Const.ExceptionCode.YEARSBELONG.getCode(),Const.ExceptionCode.YEARSBELONG.getMsg());
}
return RestResult.createBySuccess();
}
}
通过实例化对象emloyee实现持久化的操作
8.同一日志处理
建立Aspect的处理类
package com.victor.employee.aspect;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import javax.servlet.ServletRequest;
import javax.servlet.http.HttpServletRequest;
@Aspect
@Component
public class HttpAspect {
private final static Logger logger= LoggerFactory.getLogger(HttpAspect.class);
@Pointcut("execution(public * com.victor.employee.Controller.EmployeeController.findAll(..))")
public void log(){
}
@Before("log()")
public void logbefore(JoinPoint joinPoint){
ServletRequestAttributes attributes= (ServletRequestAttributes)RequestContextHolder.getRequestAttributes();
HttpServletRequest request=attributes.getRequest();
logger.info("url={}",request.getRequestURL());
logger.info("method{}",request.getMethod());
logger.info("ip={}",request.getRemoteAddr());
logger.info("classmethod={}",joinPoint.getSignature().getDeclaringTypeName()+"."+joinPoint.getSignature().getName());
logger.info("args={}",joinPoint.getArgs());
}
@After("log()")
public void logafter(){
System.out.print(2222222);
}
@AfterReturning(returning = "object",pointcut = "log()")
public void doAfterReturning(Object object){
logger.info("respond={}",object);
}
}
9.统一的异常处理
a.建立高可用的Rest接口类
RestResult‘
package com.victor.employee.common;
public class RestResult<T> {
private Integer code;
private String msg;
private T data;
private RestResult(){};
private RestResult(Integer code){
this.code=code;
}
private RestResult(Integer code,String msg){
this.code=code;
this.msg=msg;
}
private RestResult(Integer code,T data){
this.code=code;
this.data=data;
}
private RestResult(Integer code,String msg,T data){
this.code=code;
this.msg=msg;
this.data=data;
}
public boolean isSuccess(){
return this.code==RestResultEnum.SUCCESS.getCode();
}
public static <T>RestResult<T> createBySuccess(){
return new RestResult<T>(RestResultEnum.SUCCESS.getCode());
}
public static <T>RestResult<T> createBySuccess(String msg){
return new RestResult<T>(RestResultEnum.SUCCESS.getCode(),msg);
}
public static <T>RestResult<T> createBySuccess(String msg,T data){
return new RestResult<T>(RestResultEnum.SUCCESS.getCode(),msg,data);
}
public static <T>RestResult<T> createBySuccess(T data){
return new RestResult<T>(RestResultEnum.SUCCESS.getCode(),data);
}
public static <T>RestResult<T> createByError(){
return new RestResult<T>(RestResultEnum.FAILED.getCode(),RestResultEnum.FAILED.getMsg());
}
public static <T>RestResult<T> createByError(String errorMsg){
return new RestResult<T>(RestResultEnum.FAILED.getCode(),errorMsg);
}
public static <T>RestResult<T> createByError(int errorCode,String errorMsg){
return new RestResult<T>(errorCode,errorMsg);
}
public Integer getCode() {
return code;
}
public void setCode(Integer code) {
this.code = code;
}
public String getMsg() {
return msg;
}
public void setMsg(String msg) {
this.msg = msg;
}
public T getData() {
return data;
}
public void setData(T data) {
this.data = data;
}
}
RestResultEnum
package com.victor.employee.common;
public enum RestResultEnum {
SUCCESS(1,"success"),
FAILED(0,"failed");
private int code;
private String msg;
public int getCode() {
return code;
}
public String getMsg() {
return msg;
}
RestResultEnum(int code, String msg) {
this.code = code;
this.msg = msg;
}
}
建立自己异常类
LocalException：
package com.victor.employee.exception;
public class LocalException extends RuntimeException {
private Integer code;
public LocalException(int code,String msg){//还可以添加一个枚举对象
super(msg);
this.code=code;
}
public Integer getCode() {
return code;
}
public void setCode(Integer code) {
this.code = code;
}
}
建立异常 处理类
ExceptionHandle：
package com.victor.employee.exception;
import com.victor.employee.common.RestResult;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
@ControllerAdvice
public class ExceptionHandle {
private Logger logger= LoggerFactory.getLogger(ExceptionHandle.class);
@ResponseBody
@ExceptionHandler(value= Exception.class)
public RestResult handle(Exception e){
if(e instanceof LocalException){
LocalException localException=(LocalException)e;
return RestResult.createByError(localException.getCode(),localException.getMessage());
}
logger.info("系统异常",e);
return RestResult.createByError(-1,"位置错误");
}
}
常量类：
package com.victor.employee.common;
/**
* 常量类
*/
public class Const {
public enum ExceptionCode{
UNKNOWEXCEPTION(-1,"未知错误"),
SUCCESS(1,"成功"),
YEARSBELONG(100,"15以上"),
YEARSUP(101,"10岁以下");
private int code;
private String msg;
private ExceptionCode(int code,String msg){
this.code=code;
this.msg=msg;
}
public int getCode() {
return code;
}
public String getMsg() {
return msg;
}
}
}