/**
* Clear associated models' save state. After this method, the associated models of baseObj which
* data is removed from database will become unsaved.
*
* @param baseObj The record to delete.
* @param associationInfos The associated info.
*/
private void clearAssociatedModelSaveState(
DataSupport baseObj, Collection<AssociationsInfo> associationInfos) {
try {
for (AssociationsInfo associationInfo : associationInfos) {
if (associationInfo.getAssociationType() == Const.Model.MANY_TO_ONE
&& !baseObj.getClassName().equals(associationInfo.getClassHoldsForeignKey())) {
Collection<DataSupport> associatedModels = getAssociatedModels(baseObj, associationInfo);
if (associatedModels != null && !associatedModels.isEmpty()) {
for (DataSupport model : associatedModels) {
if (model != null) {
model.resetBaseObjId();
}
}
}
} else if (associationInfo.getAssociationType() == Const.Model.ONE_TO_ONE) {
DataSupport model = getAssociatedModel(baseObj, associationInfo);
if (model != null) {
model.resetBaseObjId();
}
}
}
} catch (Exception e) {
throw new DataSupportException(e.getMessage());
}
}
/**
* Delete the referenced rows of baseObj in associated tables(Many2One and One2One conditions).
*
* @param baseObj The record to delete. Now contains associations info.
* @return The number of rows affected in all associated tables.
*/
private int deleteAssociatedForeignKeyRows(DataSupport baseObj) {
int rowsAffected = 0;
Map<String, Set<Long>> associatedModelMap = baseObj.getAssociatedModelsMapWithFK();
for (String associatedTableName : associatedModelMap.keySet()) {
String fkName = getForeignKeyColumnName(baseObj.getTableName());
rowsAffected +=
mDatabase.delete(associatedTableName, fkName + " = " + baseObj.getBaseObjId(), null);
}
return rowsAffected;
}
/**
* The open interface for other classes in CRUD package to delete. Using baseObj to decide which
* record to delete. The baseObj must be saved already(using {@link
* org.litepal.crud.DataSupport#isSaved()} to test), or nothing will be deleted. This method can
* action cascade delete. When the record is deleted from database, all the referenced data such
* as foreign key value will be removed too.
*
* @param baseObj The record to delete.
* @return The number of rows affected. Including cascade delete rows.
*/
int onDelete(DataSupport baseObj) {
if (baseObj.isSaved()) {
Collection<AssociationsInfo> associationInfos = analyzeAssociations(baseObj);
int rowsAffected = deleteCascade(baseObj);
rowsAffected +=
mDatabase.delete(baseObj.getTableName(), "id = " + baseObj.getBaseObjId(), null);
clearAssociatedModelSaveState(baseObj, associationInfos);
return rowsAffected;
}
return 0;
}
/**
* Delete the referenced rows of baseObj in intermediate join tables(Many2Many condition).
*
* @param baseObj The record to delete. Now contains associations info.
* @return The number of rows affected in all intermediate join tables.
*/
private int deleteAssociatedJoinTableRows(DataSupport baseObj) {
int rowsAffected = 0;
Set<String> associatedTableNames = baseObj.getAssociatedModelsMapForJoinTable().keySet();
for (String associatedTableName : associatedTableNames) {
String joinTableName =
DBUtility.getIntermediateTableName(baseObj.getTableName(), associatedTableName);
String fkName = getForeignKeyColumnName(baseObj.getTableName());
rowsAffected +=
mDatabase.delete(joinTableName, fkName + " = " + baseObj.getBaseObjId(), null);
}
return rowsAffected;
}
/**
* Analyze the associations of baseObj and store the result in it. The associations will be used
* when deleting referenced data of baseObj.
*
* @param baseObj The record to delete.
*/
private Collection<AssociationsInfo> analyzeAssociations(DataSupport baseObj) {
try {
Collection<AssociationsInfo> associationInfos = getAssociationInfo(baseObj.getClassName());
analyzeAssociatedModels(baseObj, associationInfos);
return associationInfos;
} catch (Exception e) {
throw new DataSupportException(e.getMessage());
}
}
