我弄java连接数据库怎么老是出现错误啊？请高手回答！谢谢

package com.test.jdbc;

import java.beans.Statement;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;

import com.mysql.jdbc.Connection;

public class Testjdbc {
public static void main(String[] args)
{
String driver="com.mysql.jdbc.Driver";
String username="root";
String passwd="123";
String url="jdbc:mysql://localhost:3306/guo";
java.sql.Statement stmt=null;
java.sql.Connection cnn=null;

try {
Class.forName(driver);
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

try {
cnn=DriverManager.getConnection(url, username, passwd);

stmt=cnn.createStatement();

ResultSet rs=stmt.executeQuery("select * from animal");
String str=rs.getString(1);
System.out.println(str);
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

}

错误：
java.sql.SQLException: Before start of result set
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1073)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:987)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:982)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:927)
at com.mysql.jdbc.ResultSetImpl.checkRowPos(ResultSetImpl.java:841)
at com.mysql.jdbc.ResultSetImpl.getStringInternal(ResultSetImpl.java:5650)
at com.mysql.jdbc.ResultSetImpl.getString(ResultSetImpl.java:5570)
at com.test.jdbc.Testjdbc.main(Testjdbc.java:33)

ResultSet的游标默认在第一行的前面，你需要把它移动到第一行，像这样
package com.test.jdbc;

import java.beans.Statement;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;

import com.mysql.jdbc.Connection;

public class Testjdbc {
public static void main(String[] args)
{
String driver="com.mysql.jdbc.Driver";
String username="root";
String passwd="123";
String url="jdbc:mysql://localhost:3306/guo";
java.sql.Statement stmt=null;
java.sql.Connection cnn=null;

try {
Class.forName(driver);
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

try {
cnn=DriverManager.getConnection(url, username, passwd);

stmt=cnn.createStatement();

ResultSet rs=stmt.executeQuery("select * from animal");
if (rs.next()) {
String str=rs.getString(1);
System.out.println(str);
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

}

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