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copied!<p>Please find below simple instructions how to create hashCode, equals and toString methods using Apache commons builders.</p> <h2>hashCode</h2> <ol> <li>If two objects are equal according to the equals() method, they must have the same hashCode() value </li> <li>It is possible that two distinct objects could have the same hashCode(). </li> <li>Please use unique Business ID for the hashCode creation (it is mean that you should use some unique property that represent business entity, for example, name) </li> <li>Hibernate Entity: please do NOT use Hibernate id for the hashCode creation </li> <li><p>You may call for .appendSuper(super.hashCode()) in case your class is subclass </p> <pre> @Override public int hashCode() { return new HashCodeBuilder() .append(getName()) .toHashCode(); } </pre></li> </ol> <h2>equals</h2> <ol> <li>Please compare Business ID (it is mean that you should use some unique property that represent business entity, for example, name) </li> <li>Hibernate Entity: please do NOT compare Hibernate id </li> <li>Hibernate Entity: use getters when you access the other object field to let to Hibernate to load the property </li> <li><p>You may call for .appendSuper(super.equals(other)) in case your class is subclass </p> <pre> @Override public boolean equals(final Object other) { if (this == other) return true; if (!(other instanceof TreeNode)) return false; TreeNode castOther = (TreeNode) other; return new EqualsBuilder() .append(getName(), castOther.getName()) .isEquals(); } </pre></li> </ol> <h2>toString</h2> <ol> <li>Please ensure that toString will not throw NullPointerException. </li> <li><p>You may call for .appendSuper(super.toString()) in case your class is subclass </p> <pre> @Override public String toString() { return new ToStringBuilder(this) .append("Name", getName()) .toString(); } </pre></li> </ol>

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