1：属性的定义与使用

 定义属性：

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <junit.version>4.10</junit.version>
    </properties>

使用属性：

            <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>${junit.version}</version>
                <scope>test</scope>
            </dependency>

 2：父pom声明与子pom引入父pom

父pom:

    <groupId>org.pine.user</groupId>
    <artifactId>user-parent</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>pom</packaging>

子pom引入父pom:

<parent>
    <groupId>org.pine.user</groupId>
    <artifactId>user-parent</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <relativePath>../user-parent/pom.xml</relativePath>
  </parent>

3：依赖的管理与声明、子pom手动继承与引入依赖

    <!-- <dependencies>中的依赖，子pom会自动继承与引入 -->
    <dependencies>

    </dependencies>

    <!-- <dependencyManagement>只是对依赖进行声明与管理，子pom不会自动继承与引入，需要手动继承与引入 -->
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>${junit.version}</version>
                <scope>test</scope>
            </dependency>

            <dependency>
                <groupId>org.pine.user</groupId>
                <artifactId>user-core</artifactId>
                <version>0.0.1-SNAPSHOT</version>
            </dependency>

            <dependency>
                <groupId>org.pine.user</groupId>
                <artifactId>user-log</artifactId>
                <version>0.0.1-SNAPSHOT</version>
            </dependency>

            <!-- jfreechart -->
            <dependency>
                <groupId>org.jfree</groupId>
                <artifactId>jfreechart</artifactId>
                <version>1.5.3</version>
            </dependency>

        </dependencies>
    </dependencyManagement>       

子pom手动继承与引入依赖：
<dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
    </dependency>
    <dependency>
        <groupId>org.pine.user</groupId>
        <artifactId>user-dao</artifactId>
    </dependency>
    <dependency>
        <groupId>org.pine.user</groupId>
        <artifactId>user-log</artifactId>
    </dependency>
    <dependency>
       <groupId>log4j</groupId>
       <artifactId>log4j</artifactId>
    </dependency>
  </dependencies>

4：将依赖的聚合整合到父pom中

    <groupId>org.pine.user</groupId>
    <artifactId>user-parent</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>pom</packaging>

    <!-- 依赖的聚合：将所有模块进行聚合，统一进行编译，测试，打包，安装操作 -->
    <!-- 将依赖的聚合整合到父pom中(将依赖的聚合整合到依赖的继承中)
               这样user-parent既是做依赖的聚合，又是做依赖的继承
     -->
    <modules>
        <module>../user-core</module>
        <module>../user-log</module>
        <module>../user-dao</module>
        <module>../user-service</module>
    </modules>