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Thread: Method Invokation

  1. #1
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    Default Method Invokation

    I need help solving this please: I have TWO methods i want to execute, but i only want the both of them to be executed if any of the methods doesn't return an error! i have tried doing this:
    addButton.addActionListener(new ActionListener(){
            	public void actionPerformed(ActionEvent ev){
            		boolean valid = true;
            		String fnField = fnameField.getText();
            		String mnField = mnameField.getText();
            		String lnField = lnameField.getText();
            		String user = usnField.getText();
            		String sx = group.getSelection().getActionCommand();
            		//
            		@SuppressWarnings("deprecation")
    				String pwd = pwdField.getText();
            		//
            		String img = imagePath.getText().trim();
            		Insert ins = new Insert();
            		int numField = 0;
            		// 
            		employee emp = new employee();
            		String errCheck = emp.err("");
            		//
            		if(fnField.equals(errCheck)){
            			valid = false;
            		}
            		if(mnField.equals(errCheck)){
            			valid = false;
            		}
            		if(lnField.equals(errCheck)){
            			valid = false;
            		}
            		if(user.equals(errCheck)){
            			valid = false;
            		}
            		if(pwd.equals(errCheck)){
            			valid = false;
            		}
            		if(isNum(numField) <= 0){
            			valid = false;
            			JOptionPane.showMessageDialog(null, "The Id field must be a"
            					+ " number greater than 0!");
            		}
            		if(img.equals(errCheck)){
            			valid = false;
            			JOptionPane.showMessageDialog(null, "Please Choose an image!");
            		}
            		if(valid){
            	 **  emp.addEmployee(isNum(numField), user, pwd, fnField, mnField, lnField, sx);
                **  ins.ImageInsert(isNum(numField), (new File(img)));
            	  }
            	}
            });
    //
    errCheck() is a method i created to check for errors in my forms! But i noticed that
    ** ins.ImageInsert(isNum(numField), (new File(img))); is executed even if there's an error with this: ** emp.addEmployee(isNum(numField), user, pwd, fnField, mnField, lnField, sx);
    //
    What can i do to prevent any of them executing if there's an error generated by at least one of them?


  2. #2
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    Default Re: Method Invokation

    to prevent any of them executing if there's an error generated
    Use a boolean variable to remember if there has been an error generated. Initialize it to false, set it true if there is an error and use its value in an if statement to control whether to call the methods.

    Please edit your post and wrap your code with code tags:
    [code=java]
    <YOUR CODE HERE>
    [/code]
    to get highlighting and preserve formatting.
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: Method Invokation

    Thanks Man. But am sure that's pretty much what i did on my code as you can see! But even at that, one of the method tends to execute despite the fact that the other one returned an error. Maybe am doing something wrongly!

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    Default Re: Method Invokation

    one of the method tends to execute despite the fact that the other one returned an error.
    Where does the code use the value of the boolean to control whether or not method is called?
    What method(s) calls do you want to control based on the boolean variable's value?

    What method returned the error?

    Try to be more specific: use the method names and the variable names when describing the problem.
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: Method Invokation

    Actually the code makes use of the value of the boolean within an actionPerformed method. The objective is to check if form variables are unassigned, if the are; the errCheck() method is a method that returns a message telling the user that a field has been left empty or unfilled. But if no field is empty or blank or null as the case may be, the ImageInsert() and addEmployee() of the employee class are executed! But i noticed that one of the methods e.g the ImageInsert() method is executed even if there was an error displayed from the errCheck() method. Now the addEmployee() method adds an employee records into the `employee` table of my database,while the ImageInsert() method inserts images into the `employeeImages` table of the same database. Hope you can understand me now?

    --- Update ---

    This is my errorCheck() method:

    	public String err(String e){
    		JPanel panel = new JPanel();
    		panel.setLayout(new java.awt.FlowLayout());
    		JLabel errLabel = new JLabel();
     
    		if(e.length() == 0){
    			errLabel.setText("A field is missing!");
    			errLabel.setFont(new Font("MonoSpaced", Font.BOLD+Font.ITALIC, 13));
    			errLabel.setForeground(new Color(120,100,100));
     
    			JOptionPane.showMessageDialog(panel,errLabel, "Error", JOptionPane.OK_OPTION);
    		}
    		return e;
    	}

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    Default Re: Method Invokation

    the ImageInsert() method is executed even if there was an error
    The imageImsert() method is called if the variable: valid has a value of true. Where is the error detected and does that code set valid false and there is no other code that sets valid true after it is set false.

    This is my errorCheck() method:
    I don't see where a method named: errorCheck() is defined. I see the definition for a method named err() and I see references to a method named errCheck() and I see a variable named: errCheck.

    It is very important when talking about code to use the correct names to avoid confusion.
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: Method Invokation

    I understand what you are trying to say man, my bad! the method isn't errCheck(), the method is err(). errCheck is a variable referencing the method err(). err() is a method in a Class named employee(), i've used the emp object to call the method err(): that is; emp.err(). Where emp is an instance of the class employee.
    Sorry for the confusion - my apologies please!

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    Default Re: Method Invokation

    How does the err() method tell its caller that it found an error so that its caller can change what other methods are called?
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: Method Invokation

    Never Mind! Solved It already! Thanks Though!

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