Searching an array?

[Katie Tuffrey]

i want to search what is stored in this array:

package cwrkpackage;

public class Students{
	
	public void array()
	{
			String [][] StudentArray = new String[100][11];
			int i = 0;	
			
			StudentArray[i][0]= IdNumber;
			StudentArray[i][1]= FullName;
			StudentArray[i][2]= DateOfBirth;
			StudentArray[i][3]= TermTimeAddress;
			StudentArray[i][4]= HomeAddress;
			StudentArray[i][5]= Course;
			StudentArray[i][6]= Fees;
			StudentArray[i][7]= ClosestRelative;
			StudentArray[i][8]= Marks;
			StudentArray[i][9]= Progression;
			StudentArray[i][10]= Fees;
			
			i++;
			System.out.print(" " + StudentArray[0][5]);
							}
	
	static String IdNumber;
	static String FullName;
	static String DateOfBirth;
	static String TermTimeAddress;
	static String HomeAddress;
	static String Course;
	static String ClosestRelative;
	static String Marks;
	static String Progression;
	static String Fees;
	

	
	public static String getFees() {
		return Fees;
	}
	public static void setFees(String fees) {
		Fees = fees;
	}
	public String getIdNumber() {
		return IdNumber;
	}
	public void setId(String IdNumber) {
		Students.IdNumber = IdNumber;
	}
	public String getFullName() {
		return FullName;
	}
	public void setFullName(String fullName) {
		FullName = fullName;
	}
	public String getDateOfBirth() {
		return DateOfBirth;
	}
	public void setDateOfBirth(String dateOfBirth) {
		DateOfBirth = dateOfBirth;
	}
	public String getTermTimeAddress() {
		return TermTimeAddress;
	}
	public void setTermTimeAddress(String termTimeAddress) {
		TermTimeAddress = termTimeAddress;
	}
	public String getHomeAddress() {
		return HomeAddress;
	}
	public void setHomeAddress(String homeAddress) {
		HomeAddress = homeAddress;
	}
	public String getCourse() {
		return Course;
	}
	public void setCourse(String course) {
		Course = course;
	}
	public String getClosestRelative() {
		return ClosestRelative;
	}
	public void setClosestRelative(String closestRelative) {
		ClosestRelative = closestRelative;
	}
	public String getMarks() {
		return Marks;
	}
	public void setMarks(String marks) {
		Marks = marks;
	}
	public String getProgression() {
		return Progression;
	}
	public void setProgression(String progression) {
		Progression = progression;
	}
	
	}

i have this:

package cwrkpackage;

import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;


import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;

public class SelectStudent extends JFrame implements ActionListener {
JTextField text;
	private static final long serialVersionUID = 1L;

	public static void main(String[] args) {
		new SelectStudent();
		
	}
	
	SelectStudent() {
		
		
		this.setSize(300, 100);
		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.setTitle("Student Record System");
		this.setVisible(true);
				
		JPanel panel1 = new JPanel(new GridLayout(3,1));
		JLabel label1 = new JLabel("Please type student name:" , JLabel.CENTER);
		
		text = new JTextField(); 
				
		label1.setHorizontalTextPosition(JLabel.CENTER);
		
		
		panel1.add(label1);
		panel1.add(text);
		this.add(panel1);
			
		JButton button1 = new JButton();
		button1.setText("View Student");
		button1.addActionListener(this);
		button1.setActionCommand("View");
					
		panel1.add(button1);  
		this.add(panel1); 
       
}

	public void actionPerformed(ActionEvent e) {
            if((e.getActionCommand() == "View"))
                {        
            	String Person = text.getText();
       			for (int i = 0; i < 10; i++ )
    			{
    				if(text.equals(i));
    				{
    				System.out.println(i.get(students));
    				}
    				}
    				}
    				else
    				{
    				System.out.println("***INVALID ENTRY***");

    				}
    				
    			}
              	
	}

which does not work!!!
any tips?
i want to search for say student name and get the student profile to display.

[Tina Smith]

    public void actionPerformed(ActionEvent e) {  
            if((e.getActionCommand() == "View"))  
                {          
                    String Person = text.getText();  
                    for (int i = 0; i < 10; i++ )  
                    {  
                        if(text.equals(i));  
                        {  
                            System.out.println(i.get(students));  
                        }  
                    }  
                }  
                else  
                {  
                    System.out.println("***INVALID ENTRY***");  
                 }  
                      
            }             
    }  

What are you seeing when you run this code, and what do you expect to see?

You may want to try writing out a step-by-step of the above code... you get the name of the person you're searching for but never use it, students is not declared, you're comparing a textbox to an integer and expecting them to somehow be equal, and you're trying to acess into an...array?...list?...of your iterator?

On line 8 of your code, you declare an integer that looks like it's going to be used to iterate and fill up an array...but you don't do any looping; i will always be zero.

Also, static (line 26-35 of your code) means that a variable belongs to the class; there will never be more than one of each of these variables. Therefore if I declared two Students and gave them different values, they'd both come out with the same ones, which I doubt is what you expect.

[D. Ogranos]

It looks like you're mixing your data class (for a single student) with the array containing the student data. Don't do that. Turn your class Students into Student (single!), so each instance of the class holds data about a student. Also make sure that the fields in your student class are not static, else the values will be the same for each student!

The data class should look something like this:

public class Student {   // represents a single student

  private String fullName;
  // other fields here

  public String getFullName() {
    return fullname;
  }

  public void setFullName(String newFullName) {
    fullName = newFullName;
  }

  // getters/setters for the other fields here
}

Then you have another class, in which you have an array (or preferably, an ArrayList) of Student objects. This would be declared something like

public class AllMyStudents {

  private static final int MAX_NUMBER_STUDENTS = 50;   // max number of students

  private Student[] students;   // an array which can hold Student objects

  public void enterStudents() {
    // The array students is not defined initially, do that before you begin entering data in it!
    students = new Students[MAX_NUMBER_STUDENTS];

    // Now the array is defined, but it holds no student entries yet (every entry is null)! Lets enter some:
    Student st = new Student();
    st.setFullName("George Cloony");
    students[0] = st;

    st = new Student();
    st.setFullName("Brad Pitt");
    students[1] = st;

    // Fill in the other students here!
  }

  public Student searchStudentByFullName(String fullName) {
    for (int i = 0; i < MAX_NUMBER_STUDENTS; i++) {
      if (students[i] != null) {   // if you didn't fill all entries of the array, the rest will be null! Make sure to test for this!
        Student st = students[i];
        if (st.getFullName().equals(fullName)) {
          return st;   // return the found student
        }
      }
    }
    // We didn't find a student :(
    return null;
  }
}

I added a little method to show you how to search an array of Student objects. As you see, you need to test each entry if it actually holds a Student or if it is null. This can be avoided if you use an ArrayList instead. ArrayList works with an array internally but adapts the array size so you don't need to worry about how many Students you actually enter into it:

import java.util.ArrayList;

public class AllMyStudents {

  private ArrayList<Student> students;   // an array list for Student objects

  public void enterStudents() {
    // The array list students is not defined initially, do that before you begin entering data in it!
    students = new ArrayList<Student>();

    // Now the list is defined, but it holds no student entries yet! Lets enter some:
    Student st = new Student();
    st.setFullName("George Cloony");
    students.add(st);   // add this student to the (end of the) list

    st = new Student();
    st.setFullName("Brad Pitt");
    students.add(st);

    // Fill in the other students here!
  }

  public Student searchStudentByFullName(String fullName) {
    for (Student st : students) {   // read this as: "for each Student st in students"
      if (st.getFullName().equals(fullName)) {
        return st;
      }
    }
    return null;   // list did not contain a student with fullName
  }
}

Hope this helps.