前言

org.apache.ibatis.io.Resources工具类用于读取MyBatis的配置文件,转换成输入流，最终用于获取SqlSessionFactory。

 Reader reader = Resources.getResourceAsReader("mybatis-config.xml");
 SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(reader);

主要方法

设置默认的ClassLoader

public static void setDefaultClassLoader(ClassLoader defaultClassLoader);

获取配置文件的绝对路径

public static URL getResourceURL(String resource);
public static URL getResourceURL(ClassLoader loader, String resource);

例子：

 try {
    System.out.println("ResourceURL = " + Resources.getResourceURL("mybatis-config.xml"));
} catch (Exception ex) {
}

//输出
ResourceURL = file:/home/lgj/aProject/MyBatis/target/classes/mybatis-config.xml

获取配置文件的输入流（字节流和字符流）

//使用相对路径，也就是类路径下
//mybatis-config.xml
public static InputStream getResourceAsStream(String resource);
public static InputStream getResourceAsStream(ClassLoader loader, String resource);
 public static Reader getResourceAsReader(String resource);
 public static Reader getResourceAsReader(ClassLoader loader, String resource);
 //使用url ，也就是使用相对于根目录的路径
 //file:/home/lgj/aProject/MyBatis/target/classes/mybatis-config.xml
 public static InputStream getUrlAsStream(String urlString);
 public static Reader getUrlAsReader(String urlString)；

例子：

Reader reader = Resources.getResourceAsReader("mybatis-config.xml");

获取配置文件，返回为File对象

public static File getResourceAsFile(String resource);
public static File getResourceAsFile(ClassLoader loader, String resource);
public static File getResourceAsFile(String resource) ; 
public static File getResourceAsFile(ClassLoader loader, String resource);

获取配置文件中的Properties对象

测试时输出各个节点和内容，不确定这两个方法具体有什么用
通过相对路径

 public static Properties getResourceAsProperties(ClassLoader loader, String resource) throws IOException {
        Properties props = new Properties();
        InputStream in = getResourceAsStream(loader, resource);
        props.load(in);
        in.close();
        return props;
    }

通过绝对路径

 public static Properties getUrlAsProperties(String urlString) throws IOException {
        Properties props = new Properties();
        InputStream in = getUrlAsStream(urlString);
        props.load(in);
        in.close();
        return props;
    }

例子

try {
            Properties properties = Resources.getResourceAsProperties("mybatis-config.xml");
            Enumeration<Object> enumeration =  properties.keys();

            while (enumeration.hasMoreElements()){
                System.out.println(enumeration.nextElement());
            }

            Collection<Object> values =  properties.values();

            for(Object v:values){
                System.out.println(v);
            }


          //  properties.keys();
        } catch (Exception ex) {

        } finally {

        }

输出（注释部分出现乱码）

</settings>
</mappers>
</typeAliases>
<property
<environments
<properties
</configuration>
<transactionManager
<!DOCTYPE
<dataSource
<environment
</transactionManager>
<!--
<?xml
</dataSource>
<package
<typeAliases>
</environments>
<configuration>
</properties>
</environment>
<setting
<settings>
<mappers>
PUBLIC
"http
|
name="password" value="563739007"/>
default="development">
resource="config.properties">
type="JDBC">
configuration
type="UNPOOLED">
id="development">
å
¨å±€å¯ç”¨æˆ–ç¦ç”¨å»¶è¿ŸåŠ è½½ã€‚å½“ç¦ç”¨æ—¶ï¼Œæ‰€æœ‰å
³è”å¯¹è±¡éƒ½ä¼šå³æ—¶åŠ è½½ -->
version="1.0" encoding="UTF-8" ?>
name="com.mybatis.dao.mapper"/>
name="mapUnderscoreToCamelCase" value="true"/>
"-//mybatis.org//DTD Config 3.0//EN"
//mybatis.org/dtd/mybatis-3-config.dtd">
-->

MyBatis源码阅读–Resources工具类

文章目录

前言