Term
|
Definition
| The JDBC API is a Java API that can access any kind of tabular data, especially data stored in a Relational Database. |
|
|
Term
Create a void function, that reads and print the values from a database.
Connection string ="jdbc:myDrive:myDatabase"
parameters: user and pass
db fields: int a, string b, float c |
|
Definition
public static void readDB (String user, String pass) throws SQLException {
Connection con = DriverManager.getConnection ("jdbc:myDriver:myDatabase",user,pass);
Statement st = con.createStatement();
ResultSet rs = st.executeQuery("SELECT A,B,C FROM TABLE1");
while (rs.next()){
System.out.println(":> "+rs.getInt("A")+rs.getString("B")+rs.getFloat("C"));
}
} |
|
|
Term
| Method to count characteres in a String |
|
Definition
|
|
Term
| Method to access a character from a String. |
|
Definition
|
|
Term
| Method to get a SubString from a String. |
|
Definition
substring (int beginning, int end)
end = end -1 |
|
|
Term
| How do you compare to String? |
|
Definition
|
|
Term
| method to compare two Strings |
|
Definition
| int compareTo(String arg). Compares to String lexicographically. |
|
|
Term
int v = "ZZZ".compareTo("zzz");
v = ? |
|
Definition
|
|
Term
int v = "ZZZ".compareTo("aaa");
v = ? |
|
Definition
|
|
Term
| Method to convert to Uppercase. |
|
Definition
| String toUpperCase( String arg) |
|
|
Term
What is the result of:
"different".indexOf("f"); |
|
Definition
|
|
Term
What is the result of:
"different".split("e")[2]; |
|
Definition
|
|
Term
import javax.swing.JFrame;
public class GUI_Problem1 {
public GUI_Problem1() {
for (int i = 0; i < 3; i++) {
JFrame frame = new JFrame("Frame " + i);
frame.setSize(300, 300);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
}
What will be the result if an instance of GUI_Problem1 is created?
a- A run-time error will be produced.
b- Thress JFrames will be shown on the screen.
c- No JFrames will be shown on the screen.
d- Only one JFrame will be shown on the screen.
|
|
Definition
Answer: d
In the constructor of GUI_Problem1 three JFrame objects are created. However, these JFrame objects are not shown on the screen as "setVisible(true)" is not invoked on each of these objects. Therefore, no JFrames are observed on the screen. |
|
|
