package chap10; import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.Statement;
import java.util.Properties; public class JDBCTest {
public static void main(String[] args) {
Properties prop = null;
try {
prop=new Properties();
prop.load(JDBCTest.class.getResourceAsStream("/chap10/database.properties"));
} catch (IOException e) {
System.out.println("读取映射文件发生异常");
}
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException e) {
System.out.println("加载驱动失败");
}
try {
Connection conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/jdbc",prop);
Statement stmt=conn.createStatement();
String sql="insert into student values(3,'lee',22)";
int row=stmt.executeUpdate(sql);
System.out.println("更新了"+row+"条信息");
stmt.close();
conn.close();
} catch (Exception e) {
System.out.println("操作数据可发生异常");
} } }

Exception in thread "main" java.lang.NullPointerException
at java.util.Properties$LineReader.readLine(Unknown Source)
at java.util.Properties.load0(Unknown Source)
at java.util.Properties.load(Unknown Source)
at chap10.JDBCTest.main(JDBCTest.java:17)