spring读取property配置文件

Pom_Parent/pom.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<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>com.wsstart</groupId>
+    <artifactId>Pom_Parent</artifactId>
+    <version>1.0-SNAPSHOT</version>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-context</artifactId>
+            <version>5.1.9.RELEASE</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <version>1.18.16</version>
+        </dependency>
+
+        <dependency>
+            <groupId>com.alibaba</groupId>
+            <artifactId>druid</artifactId>
+            <version>1.1.2</version>
+        </dependency>
+    </dependencies>
+
+    <properties>
+        <maven.compiler.source>8</maven.compiler.source>
+        <maven.compiler.target>8</maven.compiler.target>
+    </properties>
+
+</project>
\ No newline at end of file

ReadProperty/pom.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<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>com.wsstart</groupId>
+    <artifactId>ReadProperty</artifactId>
+    <version>1.0-SNAPSHOT</version>
+
+    <dependencies>
+        <dependency>
+            <groupId>com.wsstart</groupId>
+            <artifactId>Pom_Parent</artifactId>
+            <version>1.0-SNAPSHOT</version>
+        </dependency>
+    </dependencies>
+
+    <properties>
+        <maven.compiler.source>8</maven.compiler.source>
+        <maven.compiler.target>8</maven.compiler.target>
+    </properties>
+
+</project>
\ No newline at end of file

ReadProperty/src/main/java/Demo.java

+import com.alibaba.druid.pool.DruidDataSource;
+import org.springframework.context.support.ClassPathXmlApplicationContext;
+
+public class Demo {
+
+    public static void main(String[] args) {
+
+        ClassPathXmlApplicationContext applicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");
+
+
+        DruidDataSource dataSource = (DruidDataSource)applicationContext.getBean("dataSource");
+
+        System.out.println(dataSource);
+    }
+}

ReadProperty/src/main/resources/applicationContext.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<beans xmlns="http://www.springframework.org/schema/beans"
+       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+       xmlns:context="http://www.springframework.org/schema/context"
+       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">
+
+
+    <import resource="classpath:jdbc.xml"></import>
+</beans>
\ No newline at end of file

ReadProperty/src/main/resources/jdbc.properties

+jdbc.driver=com.mysql.jdbc.Driver
+jdbc.url=jdbc:mysql://localhost:3306/mybatis_db
+jdbc.username=root
+jdbc.password=root
\ No newline at end of file

ReadProperty/src/main/resources/jdbc.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<beans xmlns="http://www.springframework.org/schema/beans"
+       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+       xmlns:context="http://www.springframework.org/schema/context"
+       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">
+    <context:property-placeholder location="classpath:jdbc.properties"></context:property-placeholder>
+
+    <bean class="com.alibaba.druid.pool.DruidDataSource" id="dataSource">
+        <property name="driverClassName" value="${jdbc.driver}"></property>
+        <property name="url" value="${jdbc.url}"></property>
+        <property name="username" value="${jdbc.username}"></property>
+        <property name="password" value="${jdbc.password}"></property>
+    </bean>
+</beans>
\ No newline at end of file