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copied!<p>That is because you are supplying it. You are passing <code>e.getMessage()</code> to your constructor as the only argument, customMessage. You then pass <code>customMessage</code> to its parent's constructor that takes a <code>String</code>, <code>Exception(String)</code>. In doing so, you are giving it the message to use for <code>serviceExceptionInstance.getMessage()</code>. Instead, do not pass the <code>customMessage</code> to its parent (use <code>super();</code>, which is implied if no call to a parent constructor is given and a no-arg, parent constructor exists). Then the message will be <code>null</code> as it is not supplied.</p> <p>In other words:</p> <pre><code>new ServiceException(e.getMessage()); </code></pre> <p>Creates a new <code>ServiceException</code> with the message from <code>e</code>. You pass that message to <code>Exception</code>, <code>ServiceException</code>'s parent.</p> <pre><code>super(customMessage); </code></pre> <p>In doing so, you use the single argument, <code>String</code>-based constructor of <code>Exception</code>. Passing a value to that constructor implies that you want it used when callers invoke <code>getMessage</code>. To avoid doing this, call a different parent constructor, or none at all (calling none is technically not possible, and it will implicitly do <code>super();</code> for you):</p> <pre><code>public ServiceException(String customMessage) { this.customMessage = customMessage; } </code></pre> <p>This will call <code>super();</code> for you, which means that the parent class has no message to send, and by <em>not</em> overriding <code>getMessage()</code> yourself, then it will return its default value (<code>null</code>). To be clear, <code>Exception</code> itself extends from <code>Throwable</code>, which is really the class providing this functionality, but it all stems from how you work with <code>Exception</code> as it serves as a pass-thru to <code>Throwable</code>.</p>

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