src/main/java/com/github/sebhoss/nullanalysis/Nullsafe.java

   1 /*
   2  * Copyright © 2013 Sebastian Hoß <mail@shoss.de>
   3  * This work is free. You can redistribute it and/or modify it under the
   4  * terms of the Do What The Fuck You Want To Public License, Version 2,
   5  * as published by Sam Hocevar. See http://www.wtfpl.net/ for more details.
   6  */
   7 package com.github.sebhoss.nullanalysis;
   8
   9 import org.eclipse.jdt.annotation.NonNull;
  10 import org.eclipse.jdt.annotation.Nullable;
  11
  12 /**
  13  * Utility classes which helps working with legacy (nullable) APIs.
  14  */
  15 public final class Nullsafe {
  16
  17     private Nullsafe() {
  18         // utility class
  19     }
  20
  21     /**
  22      * @param <T>
  23      *            The type of the reference
  24      * @param reference
  25      *            A possible <code>null</code> reference.
  26      * @return Either the reference itself, or an {@link NullPointerException}, in case the reference was
  27      *         <code>null</code>.
  28      */
  29     public static <T> @NonNull T nullsafe(@Nullable final T reference) {
  30         if (reference != null) {
  31             return reference;
  32         }
  33
  34         throw new NullPointerException(); // NOPMD - we want to throw NPE here
  35     }
  36
  37     /**
  38      * @param <T>
  39      *            The type of the reference
  40      * @param reference
  41      *            A possible <code>null</code> reference.
  42      * @param message
  43      *            The exception message to throw.
  44      * @return Either the reference itself, or an {@link NullPointerException}, in case the reference was
  45      *         <code>null</code>.
  46      */
  47     public static <T> @NonNull T nullsafe(@Nullable final T reference, final String message) {
  48         if (reference != null) {
  49             return reference;
  50         }
  51
  52         throw new NullPointerException(message); // NOPMD - we want to throw NPE here
  53     }
  54
  55 }