Precompute cursor indexes in DocumentsUI and improve perf by 2.7%. (b49634ed) · Commits · e / os / android_packages_apps_DocumentsUI

src/com/android/documentsui/dirlist/Model.java

+30 −26

Original line number	Diff line number	Diff line
		@@ -20,8 +20,6 @@ import static com.android.documentsui.Shared.DEBUG;
		import static com.android.documentsui.State.SORT_ORDER_DISPLAY_NAME;
		import static com.android.documentsui.State.SORT_ORDER_LAST_MODIFIED;
		import static com.android.documentsui.State.SORT_ORDER_SIZE;
		import static com.android.documentsui.model.DocumentInfo.getCursorLong;
		import static com.android.documentsui.model.DocumentInfo.getCursorString;

		import android.database.Cursor;
		import android.os.Bundle;
		@@ -62,24 +60,17 @@ public class Model {
		private String mIds[] = new String[0];
		private int mSortOrder = SORT_ORDER_DISPLAY_NAME;

		private int mAuthorityIndex = -1;
		private int mDocIdIndex = -1;
		private int mMimeTypeIndex = -1;
		private int mDisplayNameIndex = -1;
		private int mColumnSizeIndex = -1;
		private int mLastModifiedIndex = -1;

		@Nullable String info;
		@Nullable String error;
		@Nullable DocumentInfo doc;

		/**
		* Generates a Model ID for a cursor entry that refers to a document. The Model ID is a unique
		* string that can be used to identify the document referred to by the cursor.
		*
		* @param c A cursor that refers to a document.
		*/
		private static String createModelId(Cursor c) {
		// TODO: Maybe more efficient to use just the document ID, in cases where there is only one
		// authority (which should be the majority of cases).
		return createModelId(
		getCursorString(c, RootCursorWrapper.COLUMN_AUTHORITY),
		getCursorString(c, Document.COLUMN_DOCUMENT_ID));
		}

		/**
		* Generates a Model ID for a cursor entry that refers to a document. The Model ID is a unique
		* string that can be used to identify the document referred to by the cursor.
		@@ -127,6 +118,13 @@ public class Model {
		mCursor = result.cursor;
		mCursorCount = mCursor.getCount();
		mSortOrder = result.sortOrder;
		mAuthorityIndex = mCursor.getColumnIndex(RootCursorWrapper.COLUMN_AUTHORITY);
		assert(mAuthorityIndex != -1);
		mDocIdIndex = mCursor.getColumnIndex(Document.COLUMN_DOCUMENT_ID);
		mMimeTypeIndex = mCursor.getColumnIndex(Document.COLUMN_MIME_TYPE);
		mDisplayNameIndex = mCursor.getColumnIndex(Document.COLUMN_DISPLAY_NAME);
		mColumnSizeIndex = mCursor.getColumnIndex(Document.COLUMN_SIZE);

		doc = result.doc;

		updateModelData();
		@@ -173,22 +171,24 @@ public class Model {
		for (int pos = 0; pos < mCursorCount; ++pos) {
		mCursor.moveToNext();
		positions[pos] = pos;
		mIds[pos] = createModelId(mCursor);

		mimeType = getCursorString(mCursor, Document.COLUMN_MIME_TYPE);
		// Generates a Model ID for a cursor entry that refers to a document. The Model ID is a
		// unique string that can be used to identify the document referred to by the cursor.
		mIds[pos] = createModelId(getString(mAuthorityIndex), getString(mDocIdIndex));

		mimeType = getString(mMimeTypeIndex);
		isDirs[pos] = Document.MIME_TYPE_DIR.equals(mimeType);

		switch (mSortOrder) {
		case SORT_ORDER_DISPLAY_NAME:
		final String displayName = getCursorString(
		mCursor, Document.COLUMN_DISPLAY_NAME);
		displayNames[pos] = displayName;
		displayNames[pos] = getString(mDisplayNameIndex);
		break;
		case SORT_ORDER_LAST_MODIFIED:
		longValues[pos] = getLastModified(mCursor);
		longValues[pos] = getLastModified();
		break;
		case SORT_ORDER_SIZE:
		longValues[pos] = getCursorLong(mCursor, Document.COLUMN_SIZE);
		longValues[pos] = mColumnSizeIndex != -1
		? mCursor.getLong(mColumnSizeIndex) : 0;
		break;
		}
		}
		@@ -364,13 +364,17 @@ public class Model {
		}
		}

		private String getString(int columnIndex) {
		return columnIndex != -1 ? mCursor.getString(columnIndex) : null;
		}

		/**
		* @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 by date.
		*/
		long getLastModified(Cursor cursor) {
		long l = getCursorLong(mCursor, Document.COLUMN_LAST_MODIFIED);
		private long getLastModified() {
		long l = mCursor.getLong(mLastModifiedIndex);
		return (l == -1) ? Long.MAX_VALUE : l;
		}