Preconditions (More information: https://github.com/google/guava/wiki/PreconditionsExplained)

Preconditions.java

final class Preconditions {
    private Preconditions() {}

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * @param expression a boolean expression
     * @throws IllegalArgumentException if {@code expression} is false
     */
    static void checkArgument(boolean expression) {
        if (!expression) {
            throw new IllegalArgumentException();
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * @param expression a boolean expression
     * @param errorMessage the exception message to use if the check fails; will be converted to a
     *     string using {@link String#valueOf(Object)}
     * @throws IllegalArgumentException if {@code expression} is false
     */
    static void checkArgument(boolean expression, @Nullable Object errorMessage) {
        if (!expression) {
            throw new IllegalArgumentException(String.valueOf(errorMessage));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * @param expression a boolean expression
     * @param errorMessageTemplate a template for the exception message should the check fail. The
     *     message is formed by replacing each {@code %s} placeholder in the template with an
     *     argument. These are matched by position - the first {@code %s} gets {@code
     *     errorMessageArgs[0]}, etc. Unmatched arguments will be appended to the formatted message in
     *     square braces. Unmatched placeholders will be left as-is.
     * @param errorMessageArgs the arguments to be substituted into the message template. Arguments
     *     are converted to strings using {@link String#valueOf(Object)}.
     * @throws IllegalArgumentException if {@code expression} is false
     * @throws NullPointerException if the check fails and either {@code errorMessageTemplate} or
     *     {@code errorMessageArgs} is null (don't let this happen)
     */
    static void checkArgument(
            boolean expression,
            @Nullable String errorMessageTemplate,
            @Nullable Object... errorMessageArgs) {
        if (!expression) {
            throw new IllegalArgumentException(format(errorMessageTemplate, errorMessageArgs));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(boolean b, @Nullable String errorMessageTemplate, char p1) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(boolean b, @Nullable String errorMessageTemplate, int p1) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(boolean b, @Nullable String errorMessageTemplate, long p1) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(
            boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(boolean b, @Nullable String errorMessageTemplate, char p1, char p2) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(boolean b, @Nullable String errorMessageTemplate, char p1, int p2) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(boolean b, @Nullable String errorMessageTemplate, char p1, long p2) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(
            boolean b, @Nullable String errorMessageTemplate, char p1, @Nullable Object p2) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(boolean b, @Nullable String errorMessageTemplate, int p1, char p2) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(boolean b, @Nullable String errorMessageTemplate, int p1, int p2) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(boolean b, @Nullable String errorMessageTemplate, int p1, long p2) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(
            boolean b, @Nullable String errorMessageTemplate, int p1, @Nullable Object p2) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(boolean b, @Nullable String errorMessageTemplate, long p1, char p2) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(boolean b, @Nullable String errorMessageTemplate, long p1, int p2) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(boolean b, @Nullable String errorMessageTemplate, long p1, long p2) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(
            boolean b, @Nullable String errorMessageTemplate, long p1, @Nullable Object p2) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(
            boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, char p2) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(
            boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, int p2) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(
            boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, long p2) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(
            boolean b,
            @Nullable String errorMessageTemplate,
            @Nullable Object p1,
            @Nullable Object p2) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(
            boolean b,
            @Nullable String errorMessageTemplate,
            @Nullable Object p1,
            @Nullable Object p2,
            @Nullable Object p3) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2, p3));
        }
    }

    /*
     * Ensures the truth of an expression involving one or more parameters to the calling method.
     *
     * <p>See {@link #checkArgument(boolean, String, Object...)} for details.
     */
    static void checkArgument(
            boolean b,
            @Nullable String errorMessageTemplate,
            @Nullable Object p1,
            @Nullable Object p2,
            @Nullable Object p3,
            @Nullable Object p4) {
        if (!b) {
            throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2, p3, p4));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * @param expression a boolean expression
     * @throws IllegalStateException if {@code expression} is false
     */
    static void checkState(boolean expression) {
        if (!expression) {
            throw new IllegalStateException();
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * @param expression a boolean expression
     * @param errorMessage the exception message to use if the check fails; will be converted to a
     *     string using {@link String#valueOf(Object)}
     * @throws IllegalStateException if {@code expression} is false
     */
    static void checkState(boolean expression, @Nullable Object errorMessage) {
        if (!expression) {
            throw new IllegalStateException(String.valueOf(errorMessage));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * @param expression a boolean expression
     * @param errorMessageTemplate a template for the exception message should the check fail. The
     *     message is formed by replacing each {@code %s} placeholder in the template with an
     *     argument. These are matched by position - the first {@code %s} gets {@code
     *     errorMessageArgs[0]}, etc. Unmatched arguments will be appended to the formatted message in
     *     square braces. Unmatched placeholders will be left as-is.
     * @param errorMessageArgs the arguments to be substituted into the message template. Arguments
     *     are converted to strings using {@link String#valueOf(Object)}.
     * @throws IllegalStateException if {@code expression} is false
     * @throws NullPointerException if the check fails and either {@code errorMessageTemplate} or
     *     {@code errorMessageArgs} is null (don't let this happen)
     */
    static void checkState(
            boolean expression,
            @Nullable String errorMessageTemplate,
            @Nullable Object... errorMessageArgs) {
        if (!expression) {
            throw new IllegalStateException(format(errorMessageTemplate, errorMessageArgs));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(boolean b, @Nullable String errorMessageTemplate, char p1) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(boolean b, @Nullable String errorMessageTemplate, int p1) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(boolean b, @Nullable String errorMessageTemplate, long p1) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(boolean b, @Nullable String errorMessageTemplate, char p1, char p2) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(boolean b, @Nullable String errorMessageTemplate, char p1, int p2) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(boolean b, @Nullable String errorMessageTemplate, char p1, long p2) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(
            boolean b, @Nullable String errorMessageTemplate, char p1, @Nullable Object p2) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(boolean b, @Nullable String errorMessageTemplate, int p1, char p2) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(boolean b, @Nullable String errorMessageTemplate, int p1, int p2) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(boolean b, @Nullable String errorMessageTemplate, int p1, long p2) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(
            boolean b, @Nullable String errorMessageTemplate, int p1, @Nullable Object p2) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(boolean b, @Nullable String errorMessageTemplate, long p1, char p2) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(boolean b, @Nullable String errorMessageTemplate, long p1, int p2) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(boolean b, @Nullable String errorMessageTemplate, long p1, long p2) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(
            boolean b, @Nullable String errorMessageTemplate, long p1, @Nullable Object p2) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(
            boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, char p2) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(
            boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, int p2) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(
            boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, long p2) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(
            boolean b,
            @Nullable String errorMessageTemplate,
            @Nullable Object p1,
            @Nullable Object p2) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(
            boolean b,
            @Nullable String errorMessageTemplate,
            @Nullable Object p1,
            @Nullable Object p2,
            @Nullable Object p3) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2, p3));
        }
    }

    /*
     * Ensures the truth of an expression involving the state of the calling instance, but not
     * involving any parameters to the calling method.
     *
     * <p>See {@link #checkState(boolean, String, Object...)} for details.
     */
    static void checkState(
            boolean b,
            @Nullable String errorMessageTemplate,
            @Nullable Object p1,
            @Nullable Object p2,
            @Nullable Object p3,
            @Nullable Object p4) {
        if (!b) {
            throw new IllegalStateException(format(errorMessageTemplate, p1, p2, p3, p4));
        }
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * @param reference an object reference
     * @return the non-null reference that was validated
     * @throws NullPointerException if {@code reference} is null
     */
    static <T> T checkNotNull(T reference) {
        if (reference == null) {
            throw new NullPointerException();
        }
        return reference;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * @param reference an object reference
     * @param errorMessage the exception message to use if the check fails; will be converted to a
     *     string using {@link String#valueOf(Object)}
     * @return the non-null reference that was validated
     * @throws NullPointerException if {@code reference} is null
     */
    static <T> T checkNotNull(T reference, @Nullable Object errorMessage) {
        if (reference == null) {
            throw new NullPointerException(String.valueOf(errorMessage));
        }
        return reference;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * @param reference an object reference
     * @param errorMessageTemplate a template for the exception message should the check fail. The
     *     message is formed by replacing each {@code %s} placeholder in the template with an
     *     argument. These are matched by position - the first {@code %s} gets {@code
     *     errorMessageArgs[0]}, etc. Unmatched arguments will be appended to the formatted message in
     *     square braces. Unmatched placeholders will be left as-is.
     * @param errorMessageArgs the arguments to be substituted into the message template. Arguments
     *     are converted to strings using {@link String#valueOf(Object)}.
     * @return the non-null reference that was validated
     * @throws NullPointerException if {@code reference} is null
     */
    static <T> T checkNotNull(
            T reference,
            @Nullable String errorMessageTemplate,
            @Nullable Object... errorMessageArgs) {
        if (reference == null) {
            // If either of these parameters is null, the right thing happens anyway
            throw new NullPointerException(format(errorMessageTemplate, errorMessageArgs));
        }
        return reference;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(T obj, @Nullable String errorMessageTemplate, char p1) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(T obj, @Nullable String errorMessageTemplate, int p1) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(T obj, @Nullable String errorMessageTemplate, long p1) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(T obj, @Nullable String errorMessageTemplate, @Nullable Object p1) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(T obj, @Nullable String errorMessageTemplate, char p1, char p2) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(T obj, @Nullable String errorMessageTemplate, char p1, int p2) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(T obj, @Nullable String errorMessageTemplate, char p1, long p2) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(
            T obj, @Nullable String errorMessageTemplate, char p1, @Nullable Object p2) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(T obj, @Nullable String errorMessageTemplate, int p1, char p2) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(T obj, @Nullable String errorMessageTemplate, int p1, int p2) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(T obj, @Nullable String errorMessageTemplate, int p1, long p2) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(
            T obj, @Nullable String errorMessageTemplate, int p1, @Nullable Object p2) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(T obj, @Nullable String errorMessageTemplate, long p1, char p2) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(T obj, @Nullable String errorMessageTemplate, long p1, int p2) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(T obj, @Nullable String errorMessageTemplate, long p1, long p2) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(
            T obj, @Nullable String errorMessageTemplate, long p1, @Nullable Object p2) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(
            T obj, @Nullable String errorMessageTemplate, @Nullable Object p1, char p2) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(
            T obj, @Nullable String errorMessageTemplate, @Nullable Object p1, int p2) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(
            T obj, @Nullable String errorMessageTemplate, @Nullable Object p1, long p2) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(
            T obj,
            @Nullable String errorMessageTemplate,
            @Nullable Object p1,
            @Nullable Object p2) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(
            T obj,
            @Nullable String errorMessageTemplate,
            @Nullable Object p1,
            @Nullable Object p2,
            @Nullable Object p3) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2, p3));
        }
        return obj;
    }

    /*
     * Ensures that an object reference passed as a parameter to the calling method is not null.
     *
     * <p>See {@link #checkNotNull(Object, String, Object...)} for details.
     */
    static <T> T checkNotNull(
            T obj,
            @Nullable String errorMessageTemplate,
            @Nullable Object p1,
            @Nullable Object p2,
            @Nullable Object p3,
            @Nullable Object p4) {
        if (obj == null) {
            throw new NullPointerException(format(errorMessageTemplate, p1, p2, p3, p4));
        }
        return obj;
    }

    /*
     * All recent hotspots (as of 2009) *really* like to have the natural code
     *
     * if (guardExpression) {
     *    throw new BadException(messageExpression);
     * }
     *
     * refactored so that messageExpression is moved to a separate String-returning method.
     *
     * if (guardExpression) {
     *    throw new BadException(badMsg(...));
     * }
     *
     * The alternative natural refactorings into void or Exception-returning methods are much slower.
     * This is a big deal - we're talking factors of 2-8 in microbenchmarks, not just 10-20%. (This is
     * a hotspot optimizer bug, which should be fixed, but that's a separate, big project).
     *
     * The coding pattern above is heavily used in java.util, e.g. in ArrayList. There is a
     * RangeCheckMicroBenchmark in the JDK that was used to test this.
     *
     * But the methods in this class want to throw different exceptions, depending on the args, so it
     * appears that this pattern is not directly applicable. But we can use the ridiculous, devious
     * trick of throwing an exception in the middle of the construction of another exception. Hotspot
     * is fine with that.
     */

    /*
     * Ensures that {@code index} specifies a valid <i>element</i> in an array, list or string of size
     * {@code size}. An element index may range from zero, inclusive, to {@code size}, exclusive.
     *
     * @param index a user-supplied index identifying an element of an array, list or string
     * @param size the size of that array, list or string
     * @return the value of {@code index}
     * @throws IndexOutOfBoundsException if {@code index} is negative or is not less than {@code size}
     * @throws IllegalArgumentException if {@code size} is negative
     */
    static int checkElementIndex(int index, int size) {
        return checkElementIndex(index, size, "index");
    }

    /*
     * Ensures that {@code index} specifies a valid <i>element</i> in an array, list or string of size
     * {@code size}. An element index may range from zero, inclusive, to {@code size}, exclusive.
     *
     * @param index a user-supplied index identifying an element of an array, list or string
     * @param size the size of that array, list or string
     * @param desc the text to use to describe this index in an error message
     * @return the value of {@code index}
     * @throws IndexOutOfBoundsException if {@code index} is negative or is not less than {@code size}
     * @throws IllegalArgumentException if {@code size} is negative
     */
    static int checkElementIndex(int index, int size, @Nullable String desc) {
        // Carefully optimized for execution by hotspot (explanatory comment above)
        if (index < 0 || index >= size) {
            throw new IndexOutOfBoundsException(badElementIndex(index, size, desc));
        }
        return index;
    }

    private static String badElementIndex(int index, int size, String desc) {
        if (index < 0) {
            return format("%s (%s) must not be negative", desc, index);
        } else if (size < 0) {
            throw new IllegalArgumentException("negative size: " + size);
        } else { // index >= size
            return format("%s (%s) must be less than size (%s)", desc, index, size);
        }
    }

    /*
     * Ensures that {@code index} specifies a valid <i>position</i> in an array, list or string of
     * size {@code size}. A position index may range from zero to {@code size}, inclusive.
     *
     * @param index a user-supplied index identifying a position in an array, list or string
     * @param size the size of that array, list or string
     * @return the value of {@code index}
     * @throws IndexOutOfBoundsException if {@code index} is negative or is greater than {@code size}
     * @throws IllegalArgumentException if {@code size} is negative
     */
    static int checkPositionIndex(int index, int size) {
        return checkPositionIndex(index, size, "index");
    }

    /*
     * Ensures that {@code index} specifies a valid <i>position</i> in an array, list or string of
     * size {@code size}. A position index may range from zero to {@code size}, inclusive.
     *
     * @param index a user-supplied index identifying a position in an array, list or string
     * @param size the size of that array, list or string
     * @param desc the text to use to describe this index in an error message
     * @return the value of {@code index}
     * @throws IndexOutOfBoundsException if {@code index} is negative or is greater than {@code size}
     * @throws IllegalArgumentException if {@code size} is negative
     */
    static int checkPositionIndex(int index, int size, @Nullable String desc) {
        // Carefully optimized for execution by hotspot (explanatory comment above)
        if (index < 0 || index > size) {
            throw new IndexOutOfBoundsException(badPositionIndex(index, size, desc));
        }
        return index;
    }

    private static String badPositionIndex(int index, int size, String desc) {
        if (index < 0) {
            return format("%s (%s) must not be negative", desc, index);
        } else if (size < 0) {
            throw new IllegalArgumentException("negative size: " + size);
        } else { // index > size
            return format("%s (%s) must not be greater than size (%s)", desc, index, size);
        }
    }

    /*
     * Ensures that {@code start} and {@code end} specify a valid <i>positions</i> in an array, list
     * or string of size {@code size}, and are in order. A position index may range from zero to
     * {@code size}, inclusive.
     *
     * @param start a user-supplied index identifying a starting position in an array, list or string
     * @param end a user-supplied index identifying a ending position in an array, list or string
     * @param size the size of that array, list or string
     * @throws IndexOutOfBoundsException if either index is negative or is greater than {@code size},
     *     or if {@code end} is less than {@code start}
     * @throws IllegalArgumentException if {@code size} is negative
     */
    static void checkPositionIndexes(int start, int end, int size) {
        // Carefully optimized for execution by hotspot (explanatory comment above)
        if (start < 0 || end < start || end > size) {
            throw new IndexOutOfBoundsException(badPositionIndexes(start, end, size));
        }
    }

    private static String badPositionIndexes(int start, int end, int size) {
        if (start < 0 || start > size) {
            return badPositionIndex(start, size, "start index");
        }
        if (end < 0 || end > size) {
            return badPositionIndex(end, size, "end index");
        }
        // end < start
        return format("end index (%s) must not be less than start index (%s)", end, start);
    }

    /*
     * Substitutes each {@code %s} in {@code template} with an argument. These are matched by
     * position: the first {@code %s} gets {@code args[0]}, etc. If there are more arguments than
     * placeholders, the unmatched arguments will be appended to the end of the formatted message in
     * square braces.
     *
     * @param template a non-null string containing 0 or more {@code %s} placeholders.
     * @param args the arguments to be substituted into the message template. Arguments are converted
     *     to strings using {@link String#valueOf(Object)}. Arguments can be null.
     */
    // Note that this is somewhat-improperly used from Verify.java as well.
    static String format(String template, @Nullable Object... args) {
        template = String.valueOf(template); // null -> "null"

        // start substituting the arguments into the '%s' placeholders
        StringBuilder builder = new StringBuilder(template.length() + 16 * args.length);
        int templateStart = 0;
        int i = 0;
        while (i < args.length) {
            int placeholderStart = template.indexOf("%s", templateStart);
            if (placeholderStart == -1) {
                break;
            }
            builder.append(template, templateStart, placeholderStart);
            builder.append(args[i++]);
            templateStart = placeholderStart + 2;
        }
        builder.append(template, templateStart, template.length());

        // if we run out of placeholders, append the extra args in square braces
        if (i < args.length) {
            builder.append(" [");
            builder.append(args[i++]);
            while (i < args.length) {
                builder.append(", ");
                builder.append(args[i++]);
            }
            builder.append(']');
        }

        return builder.toString();
    }
}