spring boot学习2之properties配置文件读取

      在spring boot学习1 时，知道spring boot会默认读取配置application.properties。那如果我们直接在application.properties添加自定义的配置项时，如何读取？或者不想把所有的配置都放在application.properties中，而是自定义一个properties文件时，又该如何读取呢？难道还需自己写代码加载读取配置文件吗？

注：下面代码是在spring boot 1.5.2版本下写的。

pom.xml

<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.2.RELEASE</version>
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
</dependencies>

@Value

   使用@Value注入写在application.properties中的配置项
application.properties

logging.config=classpath:logback.xml
logging.path=d:/logs

##tomcat set###
server.port=80
#session 超时时间
server.session-timeout=60
###########

hello=hello china!!!

class.schoolName=china school
class.className=second grade three class
class.students[0].name=tom
class.students[1].name=jack

在代码中@Value注入到属性中

@Controller
@RequestMapping("/")
public class HelloController {

public static Logger LOG = LoggerFactory.getLogger(HelloController.class);

@Value("${hello}")
private String hello;

@Value("${class.schoolName}")
private String schoolName;

@ConfigurationProperties

 如果想把某种相关的配置，注入到某个配置类中，比如上面的application.properties中看到class.xx的配置项，想注入到ClassConfig配置类中

package com.fei.springboot.config;

import java.util.ArrayList;
import java.util.List;

import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;

@Component("classConfig")
@ConfigurationProperties(prefix="class")
public class ClassConfig {

private String schoolName;

private String className;

private List<StudentConfig> students = new ArrayList<StudentConfig>();

public String getSchoolName() {
return schoolName;
}

public void setSchoolName(String schoolName) {
this.schoolName = schoolName;
}

public void setClassName(String className) {
this.className = className;
}

public void setStudents(List<StudentConfig> students) {
this.students = students;
}

public String getClassName() {
return className;
}

public List<StudentConfig> getStudents() {
return students;
}

}

 这样就会把application.properties中以class.开头的配置项给注入进来

我们看到代码中@ConfigurationProperties并没有指明properties，那默认的就是application.properties。那是否有地方指明properties的路径呢？在版本1.5.1之前可以@ConfigurationProperties(prefix="class",location="classpath:/customer.properties")，但是1.5.2版本没有location了，需要用@PropertySource("classpath:/student.properties")

package com.fei.springboot.config;

import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.PropertySource;
import org.springframework.stereotype.Component;

@Component("studentConfig")
@ConfigurationProperties
@PropertySource("classpath:/student.properties")
public class StudentConfig {

private String name;

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

}

测试下

package com.fei.springboot.controller;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import com.fei.springboot.config.ClassConfig;
import com.fei.springboot.config.StudentConfig;

@Controller
@RequestMapping("/")
public class HelloController {

public static Logger LOG = LoggerFactory.getLogger(HelloController.class);

@Value("${hello}")
private String hello;

@Value("${class.schoolName}")
private String schoolName;

@Autowired
private ClassConfig classConfig;

@Autowired
private StudentConfig studentConfig;

@RequestMapping(value="/hello")
@ResponseBody
public String hello(){
System.out.println("=======使用@Value注入获取.....===========");
System.out.println("hello="+hello+"   schoolName=" + schoolName);
System.out.println("======使用@ConfigurationProperties注入获取.....============");
System.out.println("schoolName=" + classConfig.getSchoolName());
System.out.println("className=" + classConfig.getClassName());
System.out.println("student[0].name=" + classConfig.getStudents().get(0).getName());

System.out.println("studentConfig...name=" + studentConfig.getName());

return "hello";
}
}

打印结果

2017-05-17 15:20:49.677  INFO 72996 --- [p-nio-80-exec-1] o.s.web.servlet.DispatcherServlet        : FrameworkServlet 'dispatcherServlet': initialization completed in 19 ms
2017-05-17 15:20:49.677 [http-nio-80-exec-1] INFO  o.s.web.servlet.DispatcherServlet - FrameworkServlet 'dispatcherServlet': initialization completed in 19 ms
=======使用@Value注入获取.....===========
hello=hello china!!!   schoolName=china school
======使用@ConfigurationProperties注入获取.....============
schoolName=china school
className=second grade three class
student[0].name=tom
studentConfig...name=xiao hong

 源码下载