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Effective Java Item10

Effective Java 2nd Edition Reading Notes
Item10: Always override toString
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Returns a string representation of the object. In general, the toString method returns a string that "textually represents" this object. The result should be a concise but informative representation that is easy for a person to read. It is recommended that all subclasses override this method.
The toString method for class Object returns a string consisting of the name of the class of which the object is an instance, the at-sign character `@', and the unsigned hexadecimal representation of the hash code of the object. In other words, this method returns a string equal to the value of:
 getClass().getName() + '@' + Integer.toHexString(hashCode())
 
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/**
 * Returns the string representation of this phone number.
 * The string consists of fourteen characters whose format
 * is "(XXX) YYY-ZZZZ", where XXX is the area code, YYY is
 * the prefix, and ZZZZ is the line number.  (Each of the
 * capital letters represents a single decimal digit.)
 *
 * If any of the three parts of this phone numb


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