Java jquery.extend

gistfile1.java

    /**
     * Equivalent to jquery.extend : copy non null  properties from origin to dest if exist
     *
     * @param orig
     * @param dest
     */
    public static void extend( Object orig, Object dest )
    {
        if ( orig == null || dest == null )
        {
            throw new IllegalArgumentException( "extend: args are null" );
        }
        for ( Method method : orig.getClass().getDeclaredMethods() )
        {
            String setterMethod;
            if ( method.getName().startsWith( "get" ) )
            {
                setterMethod = method.getName().replaceFirst( "get", "set" );
            }
            else if ( method.getName().startsWith( "is" ) )
            {
                setterMethod = method.getName().replaceFirst( "is", "set" );
            }
            else
            {
                logger.debug( "skip not a getter method {}", method.getName() );
                continue;
            }
            try
            {
                Object value = method.invoke( orig );
                if ( value == null )
                {
                    logger.debug( "skip null value for method {}", method.getName() );
                    continue;
                }
                Method destMethod;
                try
                {
                    destMethod = dest.getClass().getDeclaredMethod( method.getName() );
                }
                catch ( NoSuchMethodException e1 )
                {
                    try
                    {
                        // handle possible clash between boolean primitive and object
                        // IDEs generate getter starting with get for Boolean field
                        destMethod = dest.getClass().getDeclaredMethod( method.getName().replaceFirst( "get", "is" ) );
                    }
                    catch ( NoSuchMethodException e2 )
                    {
                        logger.debug( "skip non existing method {} in dest class", method.getName() );
                        continue;
                    }
                }
                if ( !destMethod.getReturnType().isAssignableFrom( method.getReturnType() ) )
                {
                    if ( destMethod.getReturnType().isPrimitive() && destMethod.getReturnType().equals( Boolean.TYPE )
                        && method.getReturnType().equals( Boolean.class ) )
                    {
                        // handle extend Boolean to boolean
                    }
                    else
                    {
                        logger.debug( "skip non assignable method {} in dest class", method.getName() );
                        continue;
                    }
                }
                dest.getClass().getDeclaredMethod( setterMethod, destMethod.getReturnType() ).invoke( dest, value );                
            }
            catch ( Exception e )
            {
                logger.error( "exeption while extending field {} from {}", method.getName(),
                              orig.getClass().getSimpleName() );
                logger.error( "dest class {}", dest.getClass().getSimpleName() );
                logger.error( "stacktrace: ", e );
                throw new RuntimeException( e );
            }
        }
    }