Properties继承了HashTable，HashTable实现了Map
一、Properties继承的源码如下：
Properties extends Hashtable
public class Hashtable
extends Dictionary
implements Map, Cloneable, java.io.Serializable
【JavaM004—Properties的load方法】二、Properties的load方法的具体使用场景–加载数据库资源
1、DataSourceUtil 代码如下
import java.io.File;
import java.io.FileInputStream;
import java.io.FilenameFilter;
import java.io.InputStreamReader;
import java.io.Reader;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import org.springframework.context.ApplicationContext;
import org.springframework.jdbc.core.JdbcTemplate;
import com.test.BaseConfigUtil;
/**
* 加载数据源类，将${catalina.home}/ybg/conf下面的所有数据源文件加入到bean工厂中
*/
public class DataSourceUtil {/**
* 初始化
*
* @param applicationContext
*/
public static void init(ApplicationContext applicationContext) {File dataDirectory = new File(System.getProperty("catalina.home") + File.separator + "test" + File.separator + "conf");
// 数据源文件必定要是properties类型。
//过滤的文件名称以db开头，以properties结尾
File[] dataFiles = dataDirectory.listFiles(new FilenameFilter() {
@Override
public boolean accept(File dir, String name) {
String fileName = name.toLowerCase();
if (fileName.endsWith(".properties")) {
if(fileName.startsWith("db")) {
return true;
}
}return false;
}
});
try (Reader reader = new InputStreamReader(new FileInputStream(dataFiles[i]), "UTF-8")) {
Properties properties = new Properties();
properties.load(reader);
//读取数据库的.properties配置文件if (!properties.isEmpty()) {
// 建立数据源的bean
Map propertyMap = new HashMap();
propertyMap.put("driverClassName", properties.getProperty("sqlDriver"));
propertyMap.put("url",properties.getProperty("sqlUrl"));
propertyMap.put("username",properties.getProperty("sqlUsername"));
propertyMap.put("password",properties.getProperty("sqlPassword"));
propertyMap.put("initialSize",properties.getProperty("sqlInitialSize"));
propertyMap.put("maxTotal",properties.getProperty("sqlMaxTotal"));
propertyMap.put("maxIdle",properties.getProperty("sqlMaxIdle"));
propertyMap.put("maxWaitMillis",properties.getProperty("sqlMaxWaitMillis"));
BeanUtil.addBean( "org.apache.commons.dbcp2.BasicDataSource", name + "_dataSource", propertyMap, null, null, null, "close");
// 建立jdbcTemplate的bean
List referenceConstrList = new ArrayList();
referenceConstrList.add(name + "_dataSource");
BeanUtil.addBean( "org.springframework.jdbc.core.JdbcTemplate", name + "_jdbcTemplate", null, null, null, referenceConstrList, null);
LogUtil.info("load datasource file {} success!", dataFiles[i].getAbsolutePath());
}
} catch (Exception e) {
LogUtil.error("load datasource file {} fail!", dataFiles[i].getAbsolutePath());
}
}
}/**
* 获取数据源* @param datasourceFileName 数据源配置文件名
* @return
*/
public static JdbcTemplate getJdbcTemplate(String datasourceFileName) {
String id = datasourceFileName + "_jdbcTemplate";
return BeanUtil.getBean(id, JdbcTemplate.class);
}
}
2、BeanUtil代码如下
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import org.springframework.beans.factory.support.BeanDefinitionBuilder;
import org.springframework.beans.factory.support.DefaultListableBeanFactory;
import org.springframework.context.ApplicationContext;
/**
* 管理bean类
*/
public class BeanUtil {// Spring Bean 工厂
public static DefaultListableBeanFactory beanFactory;
public static void init(ApplicationContext applicationContext) {
beanFactory = (DefaultListableBeanFactory) applicationContext.getAutowireCapableBeanFactory();
}
/**
* 动态增加bean
*
* @param className
* @param beanKey
* @param propertyMap
* @param referenceMap
* @return
*/
public static boolean addBean(
String className, String beanKey, Map propertyMap,
Map referenceMap, List转自https://blog.csdn.net/u013592116/article/details/73181423
