/**
* Copyright (c) 2012 Todoroo Inc
*
* See the file "LICENSE" for the full license governing this code.
*/
package com.timsu.astrid.data;
import java.util.Date;
import java.util.HashMap;
import android.content.ContentValues;
import android.database.Cursor;
/** A data object backed by a database */
@SuppressWarnings("nls")
public abstract class LegacyAbstractModel {
/* Data Source Ordering:
*
* In order to return the best data, we want to check first what the user
* has explicitly set (setValues), then the values we have read out of
* the database (values), the database itself (cursor), then defaults
* (getDefaultValues)
*/
/** User set values */
protected ContentValues setValues = new ContentValues();
/** Cached values from database */
private final ContentValues values = new ContentValues();
/** Cursor into the database */
private Cursor cursor = null;
// --- constructors
/** Construct a model from scratch */
public LegacyAbstractModel() {
// ...
}
/** Construct a model from a database object */
public LegacyAbstractModel(Cursor cursor) {
this.cursor = cursor;
}
// --- data source getters
/** Get the user-set values for this object */
public ContentValues getSetValues() {
return setValues;
}
/** Get the default values for this object */
abstract public ContentValues getDefaultValues();
/** Get a list of all field/value pairs merged across data sources */
public ContentValues getMergedValues() {
ContentValues mergedValues = new ContentValues();
mergedValues.putAll(getDefaultValues());
mergedValues.putAll(values);
mergedValues.putAll(setValues);
return mergedValues;
}
/** Return the database cursor */
public Cursor getCursor() {
return cursor;
}
// --- checking against cached values
protected void putIfChangedFromDatabase(String field, String newValue) {
if(!setValues.containsKey(field) && values.containsKey(field)) {
String value = values.getAsString(field);
if(value == null) {
if(newValue == null)
return;
} else if(value.equals(newValue))
return;
}
setValues.put(field, newValue);
}
protected void putIfChangedFromDatabase(String field, Long newValue) {
if(!setValues.containsKey(field) && values.containsKey(field)) {
Long value = values.getAsLong(field);
if(value == null) {
if(newValue == null)
return;
} else if(value.equals(newValue))
return;
}
setValues.put(field, newValue);
}
protected void putIfChangedFromDatabase(String field, Integer newValue) {
if(!setValues.containsKey(field) && values.containsKey(field)) {
Integer value = values.getAsInteger(field);
if(value == null) {
if(newValue == null)
return;
} else if(value.equals(newValue))
return;
}
setValues.put(field, newValue);
}
protected void putIfChangedFromDatabase(String field, Double newValue) {
if(!setValues.containsKey(field) && values.containsKey(field)) {
Double value = values.getAsDouble(field);
if(value == null) {
if(newValue == null)
return;
} else if(value.equals(newValue))
return;
}
setValues.put(field, newValue);
}
protected static final HashMap<Class<?>, HashMap<String, Integer>>
columnIndexCache = new HashMap<Class<?>, HashMap<String, Integer>>();
private int getColumnIndex(String field) {
HashMap<String, Integer> classCache;
classCache = columnIndexCache.get(getClass());
if(classCache == null) {
classCache = new HashMap<String, Integer>();
columnIndexCache.put(getClass(), classCache);
}
Integer index = classCache.get(field);
if(index == null) {
index = cursor.getColumnIndexOrThrow(field);
classCache.put(field, index);
}
return index;
}
// --- data retrieval for the different object types
protected String retrieveString(String field) {
if(setValues.containsKey(field))
return setValues.getAsString(field);
if(values.containsKey(field))
return values.getAsString(field);
// if we have a database to hit, do that now
if(cursor != null) {
String value = cursor.getString(getColumnIndex(field));
values.put(field, value);
return value;
}
// do we have defaults?
ContentValues defaults = getDefaultValues();
if(defaults != null && defaults.containsKey(field))
return defaults.getAsString(field);
throw new UnsupportedOperationException("Could not read field " + field);
}
protected Integer retrieveInteger(String field) {
if(setValues.containsKey(field))
return setValues.getAsInteger(field);
if(values.containsKey(field))
return values.getAsInteger(field);
// if we have a database to hit, do that now
if(cursor != null) {
try {
Integer value = cursor.getInt(getColumnIndex(field));
values.put(field, value);
return value;
} catch (Exception e) {
// error reading from cursor, try to continue
}
}
// do we have defaults?
ContentValues defaults = getDefaultValues();
if(defaults != null && defaults.containsKey(field))
return defaults.getAsInteger(field);
throw new UnsupportedOperationException("Could not read field " + field);
}
protected Long retrieveLong(String field) {
if(setValues.containsKey(field))
return setValues.getAsLong(field);
if(values.containsKey(field))
return values.getAsLong(field);
// if we have a database to hit, do that now
if(cursor != null) {
Long value = cursor.getLong(getColumnIndex(field));
values.put(field, value);
return value;
}
// do we have defaults?
ContentValues defaults = getDefaultValues();
if(defaults != null && defaults.containsKey(field))
return defaults.getAsLong(field);
throw new UnsupportedOperationException("Could not read field " + field);
}
protected Double retrieveDouble(String field) {
if(setValues.containsKey(field))
return setValues.getAsDouble(field);
if(values.containsKey(field))
return values.getAsDouble(field);
// if we have a database to hit, do that now
if(cursor != null) {
Double value = cursor.getDouble(getColumnIndex(field));
values.put(field, value);
return value;
}
// do we have defaults?
ContentValues defaults = getDefaultValues();
if(defaults != null && defaults.containsKey(field))
return defaults.getAsDouble(field);
throw new UnsupportedOperationException("Could not read field " + field);
}
// --- retrieving composite objects
protected Date retrieveDate(String field) {
Long time;
try {
time = retrieveLong(field);
if(time == null || time == 0)
return null;
} catch (NullPointerException e) {
return null;
}
return new Date(time);
}
}