Topics

Morphing Objects
Asserting array equality

Morphing Objects

Morphing Objects is as easy as calling morph() on a Morpher or ObjectMorpher . You may have noticed that Morpher does not have a morph() method but ObjectMorpher does, that is because Morpher is used on primitive Morphers too.

Example:

  1. int i = new IntMorpher().morph( "123" );  
  2. assertEquals( 123, i ); // true!  
  3.                     
  4. String str = new StringMorpher().morph( new Integer(123) );  
  5. assertEquals( "123", str ); // true!   
  6.   
  7. Boolean[] bools = new ObjectArrayMorpher(  
  8.                         new BooleanObjectMorpher() ).morph(  
  9.                              new String[]{ "true", "false" } );  
  10. assertEquals( Boolean.TRUE, bools[0] ); // true!  
  11. assertEquals( Boolean.FALSE, bools[1] ); // true!  
  12.   
  13. // will morph a DynaBean into a MyBean instance  
  14. DynaBean dynaBean = ... // initialized elsewhere  
  15. morpherRegistry.registerMorpher( new BeanMorpher( MyBean.class, morpherRegistry ) );  
  16. MyBean myBean = (MyBean) morpherRegistry.moprh( MyBean.class, dynaBean );  
  17.   
  18. // will morph a BeanA into a BeanB, where a property of BeanB is also a property of BeanA  
  19. BeanA beanA = ... // initialized elsewhere  
  20. morpherRegistry.registerMorpher( new BeanMorpher( BeanB.class, morpherRegistry ) );  
  21. BeanB beanB = (BeanB) morpherRegistry.morph( BeanB.class, beanA );  

EZMorph comes with a handy class for working with Morphers named MorpherRegistry. It works much like ConvertUtils on commons-beanutils. This class is not a singleton like ConvertUtils, so it is possible to have multiple registries with different Morphers that support the same target class, but take different default values or support different source classes. Another convenient class is MorphUtils, you can register standard Morphers to any MorpherRegistry with it.

Example:

  1. MorpherRegistry morperRegistry = new MorpherRegistry();  
  2. MorphUtils.registerStandardMorphers( morpherRegistry );  
  3. Integer i = (Integer) morpherRegistry.morph( Integer.class, "A" );  
  4. // "A" is not a number, so morph() returns a Integer(0)  
  5. assertEquals( new Integer(0), i );  

Asserting array equality

Asserting array equality is very easy with ArrayAssertions, just call assertEquals on it, and will try to see first if the arrays reffer to the same location in memory, if not, it will compare them by value, iterating through each dimension the arrays may have.

Here are the meat and bones of every assertEquals:

  1. public static void assertEquals( String message, boolean[] expecteds, boolean[] actuals )  
  2. {  
  3.    if( expecteds == actuals ){  
  4.       return;  
  5.    }  
  6.    String header = message == null ? "" : message + ": ";  
  7.    if( expecteds == null ){  
  8.       fail( header + "expected array was null" );  
  9.    }  
  10.    if( actuals == null ){  
  11.       fail( header + "actual array was null" );  
  12.    }  
  13.    if( actuals.length != expecteds.length ){  
  14.       fail( header + "array lengths differed, expected.length=" + expecteds.length  
  15.             + " actual.length=" + actuals.length );  
  16.    }  
  17.   
  18.    for( int i = 0; i < expecteds.length; i++ ){  
  19.       assertEquals( header + "arrays first differed at element [" + i + "];", expecteds[i],  
  20.             actuals[i] );  
  21.    }  
  22. }  
assertEquals( Object[], Object[] ) is different, as it will inspect the arrays for primitive contents and call the appropriate method.