Following is the declaration for java.lang.String.hashCode() method The hashCode() method of objects is used when you insert them into a HashTable, HashMap or HashSet.. An object’s hash code allows algorithms and data structures to put objects into compartments, just like letter types in a printer’s type case. POJO. I seem to remember, back around Java 1.1 or 1.2, String's hashCode() only looked at the first 8 characters. Throws: IllegalArgumentException - if algorithm is null or key is null, empty, or too short, i.e. But the question here is, how this integer value 70472 is printed.If you will try to find the hashcode value of this string again, the result would be the same. key.length-offset Implementing equals; override – Overriding equals and hashCode in Java How to override equals() method in java For the Java String's hashcode() implementation:. I assume this was because there was some truth to the "Java is slow" mantra back then. 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