How to use the toString method in Java?

Question

Can anybody explain to me the concept of the toString() method, defined in the Object class? How is it used, and what is its purpose?

Answer 1

/**
 * This toString-Method works for every Class, where you want to display all the fields and its values
 */
public String toString() {

    StringBuffer sb = new StringBuffer();

    Field[] fields = getClass().getDeclaredFields(); //Get all fields incl. private ones

    for (Field field : fields){

        try {

            field.setAccessible(true);
            String key=field.getName();
            String value;

            try{
                value = (String) field.get(this);
            } catch (ClassCastException e){
                value="";
            }

            sb.append(key).append(": ").append(value).append("\n");

        } catch (IllegalArgumentException e) {
            e.printStackTrace();
        } catch (SecurityException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        }

    }

    return sb.toString();
}