Class Assert


  • public final class Assert
    extends Object
    Assert is useful for embedding runtime sanity checks in code. The predicate methods all test a condition and throw some type of unchecked exception if the condition does not hold.

    Assertion failure exceptions, like most runtime exceptions, are thrown when something is misbehaving. Assertion failures are invariably unspecified behavior; consequently, clients should never rely on these being thrown (and certainly should not being catching them specifically).

    This class is not intended to be instantiated or sub-classed by clients.

    • Method Detail

      • argument

        public static boolean argument​(boolean expression)
        Asserts that an argument is legal. If the given boolean is not true, an IllegalArgumentException is thrown.
        Parameters:
        expression - the expression of the check
        Returns:
        true if the check passes (does not return if the check fails)
        Throws:
        IllegalArgumentException - if the legality test failed
      • argument

        public static boolean argument​(boolean expression,
                                       String message)
        Asserts that an argument is legal. If the given boolean is not true, an IllegalArgumentException is thrown. The given message is included in that exception, to aid debugging.
        Parameters:
        expression - the result of the evaluated argument expression
        message - the message to include in the exception
        Returns:
        true if the check passes (does not return if the check fails)
        Throws:
        IllegalArgumentException - if the legality test failed
      • notNull

        public static void notNull​(Object object)
        Asserts that the given object is not null. If this is not the case, some kind of unchecked exception is thrown.
        Parameters:
        object - the value to test
        Throws:
        NullPointerException - if the object is null
      • notNull

        public static void notNull​(Object object,
                                   String message)
        Asserts that the given object is not null. If this is not the case, some kind of unchecked exception is thrown. The given message is included in that exception, to aid debugging.
        Parameters:
        object - the value to test
        message - the message to include in the exception
        Throws:
        NullPointerException - if the object is null
      • state

        public static boolean state​(boolean expression)
        Asserts that the given boolean is true. If this is not the case, some kind of unchecked exception is thrown.
        Parameters:
        expression - the result of the evaluated state expression
        Returns:
        true if the check passes (does not return if the check fails)
        Throws:
        IllegalStateException - if the given boolean is false
      • state

        public static boolean state​(boolean expression,
                                    String message)
        Asserts that the given boolean is true. If this is not the case, some kind of unchecked exception is thrown. The given message is included in that exception, to aid debugging.
        Parameters:
        expression - the result of the evaluated state expression
        message - the message to include in the exception
        Returns:
        true if the check passes (does not return if the check fails)
        Throws:
        IllegalStateException - if the given boolean is false