java框架Spring学习（一）

public interface UserDao {

void printInfo();
}

import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

public class UserDaoImpl implements UserDao{
private String jdbcUrl;
private String driverClass;
private String username;
private String password;

public UserDaoImpl() {
//读取配置文件
String resource = "jdbc.properties";
Properties props = loadProperties(resource);

//初始化信息
jdbcUrl = props.getProperty("jdbcUrl");
driverClass = props.getProperty("driverClass");
username = props.getProperty("username");
password = props.getProperty("password");

//显示信息
printInfo();
}

/**
* 加载配置文件
* @param resource
*/
private Properties loadProperties(String resource){
InputStream inputStream = null;

try {
inputStream = getClass().getResourceAsStream(resource);
/**
* 从根目录开始找
* this.getClass().getClassLoader().getResourceAsStream("");
* 从当前目录开始找
* this.getClass().getResourceAsStream("");
*/
Properties props = new Properties();
props.load(inputStream); //读配置文件
return props;
} catch (IOException e) {
throw new RuntimeException(e);
}finally{
try {
inputStream.close();//关闭流
} catch (IOException e) {
throw new RuntimeException(e);
}
}

}

public void printInfo(){
System.out.println("jdbcUrl =  "+jdbcUrl);
System.out.println("driverClass =  "+driverClass);
System.out.println("username =  "+username);
System.out.println("password =  "+password);
}

public String getJdbcUrl() {
return jdbcUrl;
}

public void setJdbcUrl(String jdbcUrl) {
this.jdbcUrl = jdbcUrl;
}

public String getDriverClass() {
return driverClass;
}

public void setDriverClass(String driverClass) {
this.driverClass = driverClass;
}

public String getUsername() {
return username;
}

public void setUsername(String username) {
this.username = username;
}

public String getPassword() {
return password;
}

public void setPassword(String password) {
this.password = password;
}

}

jdbcUrl      = jdbc:mysql:///test22
driverClass  = com.mysql.jdbc.Driver
username     = root
password     = root

import static org.junit.Assert.*;

import org.junit.Test;

public class UserDaoImplTest {

@Test
public void testUserDaoImpl() {
UserDao userDao = new UserDaoImpl();
}

}