org.faktorips.runtime

Interface IDeltaComputationOptions

All Known Implementing Classes:

DeltaComputationOptionsByPosition

public interface IDeltaComputationOptions

Callback interface for the delta computation.

Author:

Jan Ortmann

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	IDeltaComputationOptions.ComputationMethod

Method Summary

Methods

Modifier and Type	Method and Description
IDeltaComputationOptions.ComputationMethod	getMethod(String association) Returns if the delta computation computes child deltas per position/index or per object.
boolean	ignore(Class<?> clazz, String property) Returns true if the given property should be ignored in the delta computation.
boolean	isSame(IModelObject object1, IModelObject object2) Returns true if the two objects represent the same conceptual object, otherwise false.

Method Detail

getMethod

IDeltaComputationOptions.ComputationMethod getMethod(String association)

Returns if the delta computation computes child deltas per position/index or per object.

1. Example for a 1-many association:
A contract version A has three coverages c0, c1, and c2. A second version B of the same contract has a new coverage cNew inserted between coverage c0 and c1. The coverages c0, c1,and c2 are unchanged except for their position.

If this method returns IDeltaComputationOptions.ComputationMethod.BY_POSITION, the following deltas are computed. position 0: version A:c0, version B:c0 => empty delta position 1: version A:c1, version B:cNew => changed position 2: version A:c2, version B:c1 => changed position 3: version A:none, version B:c2 => added

If this method returns IDeltaComputationOptions.ComputationMethod.BY_OBJECT, the following deltas are computed. c0: version A:position 0, version B:position 0 => empty delta c1: version A:position 1, version B:position 2 => moved c2: version A:position 2, version B:position 3 => moved cNew: version A:position none, version B:position 1 => added

2. Example for a 1-many association:
Same scenario as above, but now c1 is removed and no coverage is added.

If this method returns IDeltaComputationOptions.ComputationMethod.BY_POSITION, the following deltas are computed. position 0: version A:c0, version B:c0 => empty delta position 1: version A:c1, version B:v2 => changed position 2: version A:c2, version B:none => removed

If this method returns IDeltaComputationOptions.ComputationMethod.BY_OBJECT, the following deltas are computed. c0: version A:position 0, version B:position 0 => empty delta c1: version A:position 1, version B:position none => removed c2: version A:position 2, version B:position 1 => moved

Example for a 1-1 association:
A contract version A has the insured person p0. A second contract version B has the insured person p1.

If this method returns IDeltaComputationOptions.ComputationMethod.BY_POSITION, the following delta is computed. position 0: changed

If this method returns IDeltaComputationOptions.ComputationMethod.BY_OBJECT, the following deltas are computed. p1: removed p2: added

isSame

boolean isSame(IModelObject object1,
             IModelObject object2)

Returns true if the two objects represent the same conceptual object, otherwise false. What the conceptual object is, depends on the use case in that you need the delta computation and on your object model.

If the objects are for example contract versions, they represent the same contract, just at different point in times. In this case the check has to compare the contract numbers but ignore the version numbers. If the objects are coverages you might consider them the same, if they are of the same coverage type, e.g. both are accidental damages coverages.

ignore

boolean ignore(Class<?> clazz,
             String property)

Returns true if the given property should be ignored in the delta computation. If you compare for example two versions of the same contract, you might want to ignore the different in the creation time, as otherwise two versions would always be different.

Parameters:

clazz - The class the property belongs to.

property - The name of the property.