Package edu.wisc.ssec.mcidasv.util

Class Contract

java.lang.Object
edu.wisc.ssec.mcidasv.util.Contract
public final class Contract extends Object
This is a "convenience" class--use these methods to reduce boilerplate parameter verification. For example: 
 if (str == null) {
     throw new NullPointerException("null is bad");
 }
can be replaced with 
 notNull(str, "null is bad");
Remember that these methods are used to signal an error in the calling method!

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    private
    Contract()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    static void
    checkArg(boolean expression)
    Ensures the "truth" of an expression involving parameters passed to the calling method.
    static void
    checkArg(boolean expression, Object message)
    Ensures the "truth" of an expression involving parameters passed to the calling method.
    static void
    checkArg(boolean expression, String format, Object... values)
    Ensures the "truth" of an expression involving parameters passed to the calling method.
    static void
    instanceOf(Object object, Class<?> clazz)
     
    static void
    instanceOf(Object message, Object object, Class<?> clazz)
     
    static boolean
    isInstanceOf(Object object, Class<?> clazz)
     
    static <T> List<T>
    noNulls(String message, T... objects)
     
    static <T> T
    notNull(T object)
    Deprecated.
    static <T> T
    notNull(T object, Object message)
    Deprecated.
    static <T> T
    notNull(T object, String format, Object... values)
    Ensures that a parameter passed to the calling method is not null.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

  • Method Details

    • notNull

      @Deprecated public static <T> T notNull(T object)
      Deprecated.
      Ensures that a parameter passed to the calling method is not null.
      Type Parameters:
      T - Type of object to test.
      Parameters:
      object - Object to test.
      Returns:
      object, if it is not null.
      Throws:
      NullPointerException - if object is null.

    • notNull

      @Deprecated public static <T> T notNull(T object, Object message)
      Deprecated.
      Ensures that a parameter passed to the calling method is not null.
      Type Parameters:
      T - Type of object to test.
      Parameters:
      object - Object to test.
      message - Exception message to use if object is null.
      Returns:
      object, if it is not null.
      Throws:
      NullPointerException - if object is null.

    • notNull

      public static <T> T notNull(T object, String format, Object... values)
      Ensures that a parameter passed to the calling method is not null.
      Type Parameters:
      T - Type of object to test.
      Parameters:
      object - Object to test.
      format - Template used to create an exception if object is null. Uses String.format(String, Object...).
      values - Values to use within format.
      Returns:
      object, if it is not null.
      Throws:
      NullPointerException - if object is null.

    • noNulls

      public static <T> List<T> noNulls(String message, T... objects)

    • checkArg

      public static void checkArg(boolean expression)
      Ensures the "truth" of an expression involving parameters passed to the calling method.
      Parameters:
      expression - A boolean expression to test.
      Throws:
      IllegalArgumentException - if expression is false.

    • checkArg

      public static void checkArg(boolean expression, Object message)
      Ensures the "truth" of an expression involving parameters passed to the calling method.
      Parameters:
      expression - A boolean expression to test.
      message - Exception message to use if expression is false.
      Throws:
      IllegalArgumentException - if expression is false.

    • checkArg

      public static void checkArg(boolean expression, String format, Object... values)
      Ensures the "truth" of an expression involving parameters passed to the calling method.
      Parameters:
      expression - A boolean expression to test.
      format - Template used to create an exception if expression is false. Uses String.format(String, Object...).
      values - Values to use within format.
      Throws:
      IllegalArgumentException - if expression is false.

    • instanceOf

      public static void instanceOf(Object object, Class<?> clazz)

    • instanceOf

      public static void instanceOf(Object message, Object object, Class<?> clazz)

    • isInstanceOf

      public static boolean isInstanceOf(Object object, Class<?> clazz)