@@ -0,0 +1,1083 @@
+package com.stolets.rxdiffutil.internal;%0A%0Aimport android.support.annotation.Nullable;%0A%0A/**%0A * Static convenience methods that help a method or constructor check whether it was invoked%0A * correctly.%0A *%0A * @see %3Ca href=%22https://github.com/google/guava/blob/master/guava/src/com/google/common/base/Preconditions.java%22%3C/a%3E%0A */%0Apublic final class Preconditions %7B%0A    private Preconditions() %7B%7D%0A%0A    /**%0A     * Ensures that an object reference passed as a parameter to the calling method is not null.%0A     *%0A     * @param reference    an object reference%0A     * @param errorMessage the exception message to use if the check fails; will be converted to a%0A     *                     string using %7B@link String#valueOf(Object)%7D%0A     * @return the non-null reference that was validated%0A     * @throws NullPointerException if %7B@code reference%7D is null%0A     */%0A    public static %3CT%3E T checkNotNull(T reference, @Nullable Object errorMessage) %7B%0A        if (reference == null) %7B%0A            throw new NullPointerException(String.valueOf(errorMessage));%0A        %7D%0A        return reference;%0A    %7D%0A%7D%0A

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