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String uid=jTextField.getText();
String upass=jTextField.getText();
try {
Class.forName("oracle.jdbc.driver.OracleDriver");//Òªµ¼ÈëÍⲿ°ü
Connection conn=DriverManager.getConnection("jdbc:oracle:thin:scott/tiger@localhost:1522:stuf1dbsid");//×îºóÒ»¸öÊÇoracleµÄsidºÅ
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// sql¾ä×Ó Îª select * from logindb where userid='uid' and upass='upass' ""²»ÏÔʾ ''²ÅÏÔʾ ''ÊÇsqlÓï¾äÖпò±äÁ¿µÄ
String sql="select * from logindb where userid='" + uid + "'and upass='" + upass+ "'";
// ¶¨Òåresult
PreparedStatement psmt= conn.prepareStatement(sql);
ResultSet res = psmt.executeQuery();
if(res.next())
{
TestDia t= new TestDia(null);
t.setVisible(true);
}else
{
System.out.println("login error");
}
} catch (ClassNotFoundException e1) {
e1.printStackTrace();
}
catch (SQLException e1) {
e1.printStackTrace();
}
try {
Class.forName("oracle.jdbc.driver.OracleDriver");
Connection conn=DriverManager.ge
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import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.util.Arrays;
public class NumberChange
{
private String strNum;
private String strNumChFormat;
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Double d1 = 0.005;
Double d2 = Double.parseDouble("0.005");
System.out.println(d1);
System.out.println(d1.toString());
System.out.println(d2);
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