Where did I go wrong in this code?

A few of my classes aren't passing automated tests. Unfortunately, said tests do not provide any useful information about why they failed. Here is my code for a couple of the classes. I'd really appreciate it if you could tell me where I went wrong. The comments should explain what each method is supposed to do.

public class CellPhone {
    protected String ownerName;

        public CellPhone(String owner) {
           ownerName = owner;


        }

    public String receiveCall(CellPhone sender) {
        // returns a String of the form:
        // owner's name " is receiving a call from " sender's name
        String receivingCall = ownerName + " is receiving a call from " + sender;

        return receivingCall;
    }

    public String call(CellPhone receiver) {
        // returns a String by using the receiver to invoke receiveCall
        // while passing in the current phone
        String invokingReceiveCall = receiver.receiveCall(receiver);

        return invokingReceiveCall;

    }
}

public class TextMessagingPhone extends CellPhone {
    private int availMessages;

    public TextMessagingPhone(String owner, int messageLimit) {
        // invokes the superclass constructor
        super(owner);
        // sets the new instance variable
        availMessages = messageLimit;
    }

    public TextMessagingPhone(String owner) {
        // invokes the other constructor of this class with 15 as the message limit
        this(owner, 15);
    }

    public String receiveText(TextMessagingPhone sender, String message) {
        // decreases the number of messages available to send
        availMessages--;

        // returns a String of the form:
        // owner's name " has received TEXT from " sender's name ":" message
        String receivedText = ownerName + " has received TEXT from " + sender + ":" + message;

        return receivedText;
    }

    public String sendText(TextMessagingPhone receiver, String message) {
        // decreases the number of messages available to send
        availMessages--;

        // returns a String by using the receiver to invoke receiveText
     开发者_开发问答   // while passing in the current phone and the message
        String invokingReceiveText = receiver.receiveText(receiver, message);

        return invokingReceiveText;
    }
}

When a phone makes a call, it passes the receiver as a parameter, so the receiver thinks it is receiving from itself. Also it never gets the name from the passed sender. Try:

public String receiveCall(CellPhone sender) {        
    // returns a String of the form:        
    // owner's name " is receiving a call from " sender's name        
    String receivingCall = ownerName + " is receiving a call from " + sender.getName();        
    return receivingCall;    
}

public String call(CellPhone receiver) {        
    // returns a String by using the receiver to invoke receiveCall        
    // while passing in the current phone        
    String invokingReceiveCall = receiver.receiveCall(this);        
    return invokingReceiveCall;    
}

public String getName() {
    return ownerName;
}

 public CellPhone(String owner) {

        }

You don't assign anything to ownerName...

 public CellPhone(String owner) {
            ownerName = owner;
        }

Check this

        String receivingCall = ownerName + " is receiving a call from " + sender;

You are using "sender" which is an object in the string expression. Using sender.ownerName after making it public or defining getOwnerName and using it should work. This same mistake is repeated couple more times!