| /* |
| * Copyright (C) 2016 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.documentsui.sorting; |
| |
| import static com.android.documentsui.base.DocumentInfo.getCursorLong; |
| import static com.android.documentsui.base.DocumentInfo.getCursorString; |
| |
| import android.database.AbstractCursor; |
| import android.database.Cursor; |
| import android.os.Bundle; |
| import android.provider.DocumentsContract.Document; |
| |
| import com.android.documentsui.base.Shared; |
| import com.android.documentsui.sorting.SortModel.SortDimensionId; |
| |
| /** |
| * Cursor wrapper that presents a sorted view of the underlying cursor. Handles |
| * common {@link Document} sorting modes, such as ordering directories first. |
| */ |
| class SortingCursorWrapper extends AbstractCursor { |
| private final Cursor mCursor; |
| |
| private final int[] mPosition; |
| |
| public SortingCursorWrapper(Cursor cursor, SortDimension dimension) { |
| mCursor = cursor; |
| |
| final int count = cursor.getCount(); |
| mPosition = new int[count]; |
| boolean[] isDirs = new boolean[count]; |
| String[] displayNames = null; |
| long[] longValues = null; |
| String[] ids = null; |
| |
| final @SortDimensionId int id = dimension.getId(); |
| switch (id) { |
| case SortModel.SORT_DIMENSION_ID_TITLE: |
| displayNames = new String[count]; |
| break; |
| case SortModel.SORT_DIMENSION_ID_DATE: |
| case SortModel.SORT_DIMENSION_ID_SIZE: |
| longValues = new long[count]; |
| ids = new String[count]; |
| break; |
| } |
| |
| cursor.moveToPosition(-1); |
| for (int i = 0; i < count; i++) { |
| cursor.moveToNext(); |
| mPosition[i] = i; |
| |
| final String mimeType = getCursorString(mCursor, Document.COLUMN_MIME_TYPE); |
| isDirs[i] = Document.MIME_TYPE_DIR.equals(mimeType); |
| |
| switch(id) { |
| case SortModel.SORT_DIMENSION_ID_TITLE: |
| final String displayName = getCursorString( |
| mCursor, Document.COLUMN_DISPLAY_NAME); |
| displayNames[i] = displayName; |
| break; |
| case SortModel.SORT_DIMENSION_ID_DATE: |
| longValues[i] = getLastModified(mCursor); |
| ids[i] = getCursorString(mCursor, Document.COLUMN_DOCUMENT_ID); |
| break; |
| case SortModel.SORT_DIMENSION_ID_SIZE: |
| longValues[i] = getCursorLong(mCursor, Document.COLUMN_SIZE); |
| ids[i] = getCursorString(mCursor, Document.COLUMN_DOCUMENT_ID); |
| break; |
| } |
| |
| } |
| |
| switch (id) { |
| case SortModel.SORT_DIMENSION_ID_TITLE: |
| binarySort(displayNames, isDirs, mPosition, dimension.getSortDirection()); |
| break; |
| case SortModel.SORT_DIMENSION_ID_DATE: |
| case SortModel.SORT_DIMENSION_ID_SIZE: |
| binarySort(longValues, isDirs, mPosition, ids, dimension.getSortDirection()); |
| break; |
| } |
| |
| } |
| |
| @Override |
| public void close() { |
| super.close(); |
| mCursor.close(); |
| } |
| |
| @Override |
| public boolean onMove(int oldPosition, int newPosition) { |
| return mCursor.moveToPosition(mPosition[newPosition]); |
| } |
| |
| @Override |
| public String[] getColumnNames() { |
| return mCursor.getColumnNames(); |
| } |
| |
| @Override |
| public int getCount() { |
| return mCursor.getCount(); |
| } |
| |
| @Override |
| public double getDouble(int column) { |
| return mCursor.getDouble(column); |
| } |
| |
| @Override |
| public float getFloat(int column) { |
| return mCursor.getFloat(column); |
| } |
| |
| @Override |
| public int getInt(int column) { |
| return mCursor.getInt(column); |
| } |
| |
| @Override |
| public long getLong(int column) { |
| return mCursor.getLong(column); |
| } |
| |
| @Override |
| public short getShort(int column) { |
| return mCursor.getShort(column); |
| } |
| |
| @Override |
| public String getString(int column) { |
| return mCursor.getString(column); |
| } |
| |
| @Override |
| public int getType(int column) { |
| return mCursor.getType(column); |
| } |
| |
| @Override |
| public boolean isNull(int column) { |
| return mCursor.isNull(column); |
| } |
| |
| @Override |
| public Bundle getExtras() { |
| return mCursor.getExtras(); |
| } |
| |
| /** |
| * @return Timestamp for the given document. Some docs (e.g. active downloads) have a null |
| * timestamp - these will be replaced with MAX_LONG so that such files get sorted to the top |
| * when sorting descending by date. |
| */ |
| private static long getLastModified(Cursor cursor) { |
| long l = getCursorLong(cursor, Document.COLUMN_LAST_MODIFIED); |
| return (l == -1) ? Long.MAX_VALUE : l; |
| } |
| |
| /** |
| * Borrowed from TimSort.binarySort(), but modified to sort two column |
| * dataset. |
| */ |
| private static void binarySort( |
| String[] sortKey, |
| boolean[] isDirs, |
| int[] positions, |
| @SortDimension.SortDirection int direction) { |
| final int count = positions.length; |
| for (int start = 1; start < count; start++) { |
| final int pivotPosition = positions[start]; |
| final String pivotValue = sortKey[start]; |
| final boolean pivotIsDir = isDirs[start]; |
| |
| int left = 0; |
| int right = start; |
| |
| while (left < right) { |
| int mid = (left + right) >>> 1; |
| |
| // Directories always go in front. |
| int compare = 0; |
| final boolean rhsIsDir = isDirs[mid]; |
| if (pivotIsDir && !rhsIsDir) { |
| compare = -1; |
| } else if (!pivotIsDir && rhsIsDir) { |
| compare = 1; |
| } else { |
| final String lhs = pivotValue; |
| final String rhs = sortKey[mid]; |
| switch (direction) { |
| case SortDimension.SORT_DIRECTION_ASCENDING: |
| compare = Shared.compareToIgnoreCaseNullable(lhs, rhs); |
| break; |
| case SortDimension.SORT_DIRECTION_DESCENDING: |
| compare = -Shared.compareToIgnoreCaseNullable(lhs, rhs); |
| break; |
| default: |
| throw new IllegalArgumentException( |
| "Unknown sorting direction: " + direction); |
| } |
| } |
| |
| if (compare < 0) { |
| right = mid; |
| } else { |
| left = mid + 1; |
| } |
| } |
| |
| int n = start - left; |
| switch (n) { |
| case 2: |
| positions[left + 2] = positions[left + 1]; |
| sortKey[left + 2] = sortKey[left + 1]; |
| isDirs[left + 2] = isDirs[left + 1]; |
| case 1: |
| positions[left + 1] = positions[left]; |
| sortKey[left + 1] = sortKey[left]; |
| isDirs[left + 1] = isDirs[left]; |
| break; |
| default: |
| System.arraycopy(positions, left, positions, left + 1, n); |
| System.arraycopy(sortKey, left, sortKey, left + 1, n); |
| System.arraycopy(isDirs, left, isDirs, left + 1, n); |
| } |
| |
| positions[left] = pivotPosition; |
| sortKey[left] = pivotValue; |
| isDirs[left] = pivotIsDir; |
| } |
| } |
| |
| /** |
| * Borrowed from TimSort.binarySort(), but modified to sort two column |
| * dataset. |
| */ |
| private static void binarySort( |
| long[] sortKey, |
| boolean[] isDirs, |
| int[] positions, |
| String[] ids, |
| @SortDimension.SortDirection int direction) { |
| final int count = positions.length; |
| for (int start = 1; start < count; start++) { |
| final int pivotPosition = positions[start]; |
| final long pivotValue = sortKey[start]; |
| final boolean pivotIsDir = isDirs[start]; |
| final String pivotId = ids[start]; |
| |
| int left = 0; |
| int right = start; |
| |
| while (left < right) { |
| int mid = ((left + right) >>> 1); |
| |
| // Directories always go in front. |
| int compare = 0; |
| final boolean rhsIsDir = isDirs[mid]; |
| if (pivotIsDir && !rhsIsDir) { |
| compare = -1; |
| } else if (!pivotIsDir && rhsIsDir) { |
| compare = 1; |
| } else { |
| final long lhs = pivotValue; |
| final long rhs = sortKey[mid]; |
| switch (direction) { |
| case SortDimension.SORT_DIRECTION_ASCENDING: |
| compare = Long.compare(lhs, rhs); |
| break; |
| case SortDimension.SORT_DIRECTION_DESCENDING: |
| compare = -Long.compare(lhs, rhs); |
| break; |
| default: |
| throw new IllegalArgumentException( |
| "Unknown sorting direction: " + direction); |
| } |
| } |
| |
| // If numerical comparison yields a tie, use document ID as a tie breaker. This |
| // will yield stable results even if incoming items are continually shuffling and |
| // have identical numerical sort keys. One common example of this scenario is seen |
| // when sorting a set of active downloads by mod time. |
| if (compare == 0) { |
| compare = pivotId.compareTo(ids[mid]); |
| } |
| |
| if (compare < 0) { |
| right = mid; |
| } else { |
| left = mid + 1; |
| } |
| } |
| |
| int n = start - left; |
| switch (n) { |
| case 2: |
| positions[left + 2] = positions[left + 1]; |
| sortKey[left + 2] = sortKey[left + 1]; |
| isDirs[left + 2] = isDirs[left + 1]; |
| ids[left + 2] = ids[left + 1]; |
| case 1: |
| positions[left + 1] = positions[left]; |
| sortKey[left + 1] = sortKey[left]; |
| isDirs[left + 1] = isDirs[left]; |
| ids[left + 1] = ids[left]; |
| break; |
| default: |
| System.arraycopy(positions, left, positions, left + 1, n); |
| System.arraycopy(sortKey, left, sortKey, left + 1, n); |
| System.arraycopy(isDirs, left, isDirs, left + 1, n); |
| System.arraycopy(ids, left, ids, left + 1, n); |
| } |
| |
| positions[left] = pivotPosition; |
| sortKey[left] = pivotValue; |
| isDirs[left] = pivotIsDir; |
| ids[left] = pivotId; |
| } |
| } |
| } |