Refactor BaseKeyboardParser as Recursive Descendent Parser
Bug: 3082538
Change-Id: Ic0d72c6fe08cfc20db86aeffb10a27efe678095e
diff --git a/java/src/com/android/inputmethod/latin/BaseKeyboard.java b/java/src/com/android/inputmethod/latin/BaseKeyboard.java
index 517bfbf..cb41ad0 100644
--- a/java/src/com/android/inputmethod/latin/BaseKeyboard.java
+++ b/java/src/com/android/inputmethod/latin/BaseKeyboard.java
@@ -121,7 +121,7 @@
/**
* Container for keys in the keyboard. All keys in a row are at the same Y-coordinate.
- * Some of the key size defaults can be overridden per row from what the {@link Keyboard}
+ * Some of the key size defaults can be overridden per row from what the {@link BaseKeyboard}
* defines.
*/
public static class Row {
@@ -135,7 +135,7 @@
public int verticalGap;
/**
* Edge flags for this row of keys. Possible values that can be assigned are
- * {@link Keyboard#EDGE_TOP EDGE_TOP} and {@link Keyboard#EDGE_BOTTOM EDGE_BOTTOM}
+ * {@link BaseKeyboard#EDGE_TOP EDGE_TOP} and {@link BaseKeyboard#EDGE_BOTTOM EDGE_BOTTOM}
*/
public int rowEdgeFlags;
@@ -217,8 +217,8 @@
/**
* Flags that specify the anchoring to edges of the keyboard for detecting touch events
* that are just out of the boundary of the key. This is a bit mask of
- * {@link Keyboard#EDGE_LEFT}, {@link Keyboard#EDGE_RIGHT}, {@link Keyboard#EDGE_TOP} and
- * {@link Keyboard#EDGE_BOTTOM}.
+ * {@link BaseKeyboard#EDGE_LEFT}, {@link BaseKeyboard#EDGE_RIGHT},
+ * {@link BaseKeyboard#EDGE_TOP} and {@link BaseKeyboard#EDGE_BOTTOM}.
*/
public int edgeFlags;
/** Whether this is a modifier key, such as Shift or Alt */
@@ -274,7 +274,7 @@
* the XML parser.
* @param res resources associated with the caller's context
* @param parent the row that this key belongs to. The row must already be attached to
- * a {@link Keyboard}.
+ * a {@link BaseKeyboard}.
* @param x the x coordinate of the top-left
* @param y the y coordinate of the top-left
* @param parser the XML parser containing the attributes for this key
diff --git a/java/src/com/android/inputmethod/latin/BaseKeyboardParser.java b/java/src/com/android/inputmethod/latin/BaseKeyboardParser.java
index b718c14..628e764 100644
--- a/java/src/com/android/inputmethod/latin/BaseKeyboardParser.java
+++ b/java/src/com/android/inputmethod/latin/BaseKeyboardParser.java
@@ -24,13 +24,58 @@
import android.content.res.Resources;
import android.content.res.TypedArray;
import android.content.res.XmlResourceParser;
+import android.util.Log;
import android.util.TypedValue;
import android.util.Xml;
import android.view.InflateException;
import java.io.IOException;
+import java.util.List;
+/**
+ * Parser for BaseKeyboard.
+ *
+ * This class parses Keyboard XML file and fill out keys in BaseKeyboard.
+ * The Keyboard XML file looks like:
+ * <pre>
+ * >!-- xml/keyboard.xml --<
+ * >Keyboard keyboard_attributes*<
+ * >!-- Keyboard Content --<
+ * >Row row_attributes*<
+ * >!-- Row Content --<
+ * >Key key_attributes* /<
+ * >Spacer horizontalGap="0.2in" /<
+ * >include keyboardLayout="@xml/other_keys"<
+ * ...
+ * >/Row<
+ * >include keyboardLayout="@xml/other_rows"<
+ * ...
+ * >/Keyboard<
+ * </pre>
+ * The xml file which is included in other file must have >merge< as root element, such as:
+ * <pre>
+ * >!-- xml/other_keys.xml --<
+ * >merge<
+ * >Key key_attributes* /<
+ * ...
+ * >/merge<
+ * </pre>
+ * and
+ * <pre>
+ * >!-- xml/other_rows.xml --<
+ * >merge<
+ * >Row row_attributes*<
+ * >Key key_attributes* /<
+ * >/Row<
+ * ...
+ * >/merge<
+ * </pre>
+ */
public class BaseKeyboardParser {
+ private static final String TAG = "BaseKeyboardParser";
+ private static final boolean DEBUG_TAG = false;
+ private static final boolean DEBUG_PARSER = false;
+
// Keyboard XML Tags
private static final String TAG_KEYBOARD = "Keyboard";
private static final String TAG_ROW = "Row";
@@ -63,71 +108,216 @@
public void parseKeyboard(XmlResourceParser parser)
throws XmlPullParserException, IOException {
- final BaseKeyboard keyboard = mKeyboard;
- Key key = null;
+ if (DEBUG_PARSER) debugEnterMethod("parseKeyboard", false);
+ int event;
+ while ((event = parser.next()) != XmlResourceParser.END_DOCUMENT) {
+ if (event == XmlResourceParser.START_TAG) {
+ final String tag = parser.getName();
+ if (DEBUG_TAG) debugStartTag("parseKeyboard", tag, false);
+ if (TAG_KEYBOARD.equals(tag)) {
+ parseKeyboardAttributes(parser);
+ parseKeyboardContent(parser, mKeyboard.getKeys());
+ break;
+ } else {
+ throw new IllegalStartTag(parser, TAG_KEYBOARD);
+ }
+ }
+ }
+ if (DEBUG_PARSER) debugLeaveMethod("parseKeyboard", false);
+ }
+ private void parseKeyboardAttributes(XmlResourceParser parser) {
+ final BaseKeyboard keyboard = mKeyboard;
+ final TypedArray a = mResources.obtainAttributes(Xml.asAttributeSet(parser),
+ R.styleable.BaseKeyboard);
+ final int width = keyboard.getKeyboardWidth();
+ final int height = keyboard.getKeyboardHeight();
+ keyboard.setKeyWidth(getDimensionOrFraction(a,
+ R.styleable.BaseKeyboard_keyWidth, width, width / 10));
+ keyboard.setKeyHeight(getDimensionOrFraction(a,
+ R.styleable.BaseKeyboard_keyHeight, height, 50));
+ keyboard.setHorizontalGap(getDimensionOrFraction(a,
+ R.styleable.BaseKeyboard_horizontalGap, width, 0));
+ keyboard.setVerticalGap(getDimensionOrFraction(a,
+ R.styleable.BaseKeyboard_verticalGap, height, 0));
+ a.recycle();
+ }
+
+ private void parseKeyboardContent(XmlResourceParser parser, final List<Key> keys)
+ throws XmlPullParserException, IOException {
+ if (DEBUG_PARSER) debugEnterMethod("parseKeyboardContent", keys == null);
+ int event;
+ while ((event = parser.next()) != XmlResourceParser.END_DOCUMENT) {
+ if (event == XmlResourceParser.START_TAG) {
+ final String tag = parser.getName();
+ if (DEBUG_TAG) debugStartTag("parseKeyboardContent", tag, keys == null);
+ if (TAG_ROW.equals(tag)) {
+ Row row = mKeyboard.createRowFromXml(mResources, parser);
+ if (keys != null && maybeStartRow(row)) {
+ parseRowContent(parser, row, keys);
+ } else {
+ // Skip entire <Row></Row>
+ parseRowContent(parser, row, null);
+ }
+ } else if (TAG_INCLUDE.equals(tag)) {
+ parseIncludeKeyboardContent(parser, keys);
+ } else {
+ throw new IllegalStartTag(parser, TAG_ROW);
+ }
+ } else if (event == XmlResourceParser.END_TAG) {
+ final String tag = parser.getName();
+ if (DEBUG_TAG) debugEndTag("parseKeyboardContent", tag, keys == null);
+ if (TAG_KEYBOARD.equals(tag)) {
+ endKeyboard(mKeyboard.getVerticalGap());
+ break;
+ } else if (TAG_MERGE.equals(tag)) {
+ break;
+ } else {
+ throw new IllegalEndTag(parser, TAG_ROW);
+ }
+ }
+ }
+ if (DEBUG_PARSER) debugLeaveMethod("parseKeyboardContent", keys == null);
+ }
+
+ private void parseRowContent(XmlResourceParser parser, Row row, List<Key> keys)
+ throws XmlPullParserException, IOException {
+ if (DEBUG_PARSER) debugEnterMethod("parseRowContent", keys == null);
+ int event;
+ while ((event = parser.next()) != XmlResourceParser.END_DOCUMENT) {
+ if (event == XmlResourceParser.START_TAG) {
+ final String tag = parser.getName();
+ if (DEBUG_TAG) debugStartTag("parseRowContent", tag, keys == null);
+ if (TAG_KEY.equals(tag)) {
+ parseKey(parser, row, keys);
+ } else if (TAG_SPACER.equals(tag)) {
+ parseSpacer(parser, keys);
+ } else if (TAG_INCLUDE.equals(tag)) {
+ parseIncludeRowContent(parser, row, keys);
+ } else {
+ throw new IllegalStartTag(parser, TAG_KEY);
+ }
+ } else if (event == XmlResourceParser.END_TAG) {
+ final String tag = parser.getName();
+ if (DEBUG_TAG) debugEndTag("parseRowContent", tag, keys == null);
+ if (TAG_ROW.equals(tag)) {
+ if (keys != null)
+ endRow();
+ break;
+ } else if (TAG_MERGE.equals(tag)) {
+ break;
+ } else {
+ throw new IllegalEndTag(parser, TAG_KEY);
+ }
+ }
+ }
+ if (DEBUG_PARSER) debugLeaveMethod("parseRowContent", keys == null);
+ }
+
+ private void parseKey(XmlResourceParser parser, Row row, List<Key> keys)
+ throws XmlPullParserException, IOException {
+ if (DEBUG_PARSER) debugEnterMethod("parseKey", keys == null);
+ if (keys == null) {
+ checkEndTag(TAG_KEY, parser);
+ } else {
+ Key key = mKeyboard.createKeyFromXml(mResources, row, mCurrentX, mCurrentY, parser);
+ checkEndTag(TAG_KEY, parser);
+ keys.add(key);
+ if (key.codes[0] == BaseKeyboard.KEYCODE_SHIFT)
+ mKeyboard.getShiftKeys().add(key);
+ endKey(key);
+ }
+ }
+
+ private void parseSpacer(XmlResourceParser parser, List<Key> keys)
+ throws XmlPullParserException, IOException {
+ if (DEBUG_PARSER) debugEnterMethod("parseSpacer", keys == null);
+ if (keys == null) {
+ checkEndTag(TAG_SPACER, parser);
+ } else {
+ final TypedArray a = mResources.obtainAttributes(Xml.asAttributeSet(parser),
+ R.styleable.BaseKeyboard);
+ int gap = getDimensionOrFraction(a, R.styleable.BaseKeyboard_horizontalGap,
+ mKeyboard.getKeyboardWidth(), 0);
+ a.recycle();
+ checkEndTag(TAG_SPACER, parser);
+ setSpacer(gap);
+ }
+ }
+
+ private void parseIncludeKeyboardContent(XmlResourceParser parser, List<Key> keys)
+ throws XmlPullParserException, IOException {
+ parseIncludeInternal(parser, null, keys);
+ }
+
+ private void parseIncludeRowContent(XmlResourceParser parser, Row row, List<Key> keys)
+ throws XmlPullParserException, IOException {
+ parseIncludeInternal(parser, row, keys);
+ }
+
+ private void parseIncludeInternal(XmlResourceParser parser, Row row, List<Key> keys)
+ throws XmlPullParserException, IOException {
+ if (DEBUG_PARSER) debugEnterMethod("parseInclude", keys == null);
+ if (keys == null) {
+ checkEndTag(TAG_INCLUDE, parser);
+ } else {
+ final TypedArray a = mResources.obtainAttributes(Xml.asAttributeSet(parser),
+ R.styleable.BaseKeyboard_Include);
+ final int keyboardLayout = a.getResourceId(
+ R.styleable.BaseKeyboard_Include_keyboardLayout, 0);
+ a.recycle();
+
+ checkEndTag(TAG_INCLUDE, parser);
+ if (keyboardLayout == 0)
+ throw new ParseException("No keyboardLayout attribute in <include/>", parser);
+ parseMerge(mResources.getLayout(keyboardLayout), row, keys);
+ }
+ if (DEBUG_PARSER) debugLeaveMethod("parseInclude", keys == null);
+ }
+
+ private void parseMerge(XmlResourceParser parser, Row row, List<Key> keys)
+ throws XmlPullParserException, IOException {
+ if (DEBUG_PARSER) debugEnterMethod("parseMerge", keys == null);
int event;
while ((event = parser.next()) != XmlResourceParser.END_DOCUMENT) {
if (event == XmlResourceParser.START_TAG) {
String tag = parser.getName();
- if (TAG_ROW.equals(tag)) {
- // TODO createRowFromXml should not be called from
- // BaseKeyboard constructor.
- Row row = keyboard.createRowFromXml(mResources, parser);
- if (!startRow(row))
- skipToEndOfRow(parser);
- } else if (TAG_KEY.equals(tag)) {
- // TODO createKeyFromXml should not be called from
- // BaseKeyboard constructor.
- key = keyboard.createKeyFromXml(mResources, mCurrentRow, mCurrentX, mCurrentY,
- parser);
- keyboard.getKeys().add(key);
- if (key.codes[0] == BaseKeyboard.KEYCODE_SHIFT)
- keyboard.getShiftKeys().add(key);
- } else if (TAG_SPACER.equals(tag)) {
- parseSpacerAttribute(parser);
- } else if (TAG_KEYBOARD.equals(tag)) {
- parseKeyboardAttributes(parser);
- } else if (TAG_INCLUDE.equals(tag)) {
- if (parser.getDepth() == 0)
- throw new InflateException("<include /> cannot be the root element");
- parseInclude(parser);
- } else if (TAG_MERGE.equals(tag)) {
- throw new InflateException(
- "<merge> must not be appeared in keyboard XML file");
+ if (DEBUG_TAG) debugStartTag("parseMerge", tag, keys == null);
+ if (TAG_MERGE.equals(tag)) {
+ if (row == null) {
+ parseKeyboardContent(parser, keys);
+ } else {
+ parseRowContent(parser, row, keys);
+ }
+ break;
} else {
- throw new InflateException("unknown start tag: " + tag);
- }
- } else if (event == XmlResourceParser.END_TAG) {
- String tag = parser.getName();
- if (TAG_KEY.equals(tag)) {
- endKey(key);
- } else if (TAG_ROW.equals(tag)) {
- endRow();
- } else if (TAG_SPACER.equals(tag)) {
- ;
- } else if (TAG_KEYBOARD.equals(tag)) {
- endKeyboard(mKeyboard.getVerticalGap());
- } else if (TAG_INCLUDE.equals(tag)) {
- ;
- } else if (TAG_MERGE.equals(tag)) {
- return;
- } else {
- throw new InflateException("unknown end tag: " + tag);
+ throw new ParseException(
+ "Included keyboard layout must have <merge> root element", parser);
}
}
}
+ if (DEBUG_PARSER) debugLeaveMethod("parseMerge", keys == null);
+ }
+
+ private static void checkEndTag(String tag, XmlResourceParser parser)
+ throws XmlPullParserException, IOException {
+ if (parser.next() == XmlResourceParser.END_TAG && tag.equals(parser.getName()))
+ return;
+ throw new NonEmptyTag(tag, parser);
}
// return true if the row is valid for this keyboard mode
- private boolean startRow(Row row) {
- mCurrentX = 0;
- mCurrentRow = row;
- return row.mode == 0 || row.mode == mKeyboard.getKeyboardMode();
- }
-
- private void skipRow() {
- mCurrentRow = null;
+ private boolean maybeStartRow(Row row) {
+ if (DEBUG_TAG)
+ Log.d(TAG, String.format("startRow: mode=0x%08x keyboardMode=0x%08x",
+ row.mode, mKeyboard.getKeyboardMode()));
+ if (row.mode == 0 || row.mode == mKeyboard.getKeyboardMode()) {
+ mCurrentX = 0;
+ mCurrentRow = row;
+ return true;
+ } else {
+ return false;
+ }
}
private void endRow() {
@@ -151,73 +341,6 @@
mCurrentX += gap;
}
- private void parseSpacerAttribute(XmlResourceParser parser) {
- final TypedArray a = mResources.obtainAttributes(Xml.asAttributeSet(parser),
- R.styleable.BaseKeyboard);
- int gap = getDimensionOrFraction(a, R.styleable.BaseKeyboard_horizontalGap,
- mKeyboard.getKeyboardWidth(), 0);
- a.recycle();
- setSpacer(gap);
- }
-
- private void parseInclude(XmlResourceParser parent)
- throws XmlPullParserException, IOException {
- final TypedArray a = mResources.obtainAttributes(Xml.asAttributeSet(parent),
- R.styleable.BaseKeyboard_Include);
- final int keyboardLayout = a.getResourceId(
- R.styleable.BaseKeyboard_Include_keyboardLayout, 0);
- a.recycle();
- if (keyboardLayout == 0)
- throw new InflateException("<include /> must have keyboardLayout attribute");
- final XmlResourceParser parser = mResources.getLayout(keyboardLayout);
-
- int event;
- while ((event = parser.next()) != XmlResourceParser.END_DOCUMENT) {
- if (event == XmlResourceParser.START_TAG) {
- String name = parser.getName();
- if (TAG_MERGE.equals(name)) {
- parseKeyboard(parser);
- return;
- } else {
- throw new InflateException(
- "include keyboard layout must have <merge> root element");
- }
- }
- }
- }
-
- private void skipToEndOfRow(XmlResourceParser parser)
- throws XmlPullParserException, IOException {
- int event;
- while ((event = parser.next()) != XmlResourceParser.END_DOCUMENT) {
- if (event == XmlResourceParser.END_TAG) {
- String tag = parser.getName();
- if (TAG_ROW.equals(tag)) {
- skipRow();
- return;
- }
- }
- }
- throw new InflateException("can not find </Row>");
- }
-
- private void parseKeyboardAttributes(XmlResourceParser parser) {
- final BaseKeyboard keyboard = mKeyboard;
- final TypedArray a = mResources.obtainAttributes(Xml.asAttributeSet(parser),
- R.styleable.BaseKeyboard);
- final int width = keyboard.getKeyboardWidth();
- final int height = keyboard.getKeyboardHeight();
- keyboard.setKeyWidth(getDimensionOrFraction(a,
- R.styleable.BaseKeyboard_keyWidth, width, width / 10));
- keyboard.setKeyHeight(getDimensionOrFraction(a,
- R.styleable.BaseKeyboard_keyHeight, height, 50));
- keyboard.setHorizontalGap(getDimensionOrFraction(a,
- R.styleable.BaseKeyboard_horizontalGap, width, 0));
- keyboard.setVerticalGap(getDimensionOrFraction(a,
- R.styleable.BaseKeyboard_verticalGap, height, 0));
- a.recycle();
- }
-
public static int getDimensionOrFraction(TypedArray a, int index, int base, int defValue) {
final TypedValue value = a.peekValue(index);
if (value == null)
@@ -230,4 +353,48 @@
}
return defValue;
}
-}
+
+ @SuppressWarnings("serial")
+ private static class ParseException extends InflateException {
+ public ParseException(String msg, XmlResourceParser parser) {
+ super(msg + " at line " + parser.getLineNumber());
+ }
+ }
+
+ @SuppressWarnings("serial")
+ private static class IllegalStartTag extends ParseException {
+ public IllegalStartTag(XmlResourceParser parser, String parent) {
+ super("Illegal start tag " + parser.getName() + " in " + parent, parser);
+ }
+ }
+
+ @SuppressWarnings("serial")
+ private static class IllegalEndTag extends ParseException {
+ public IllegalEndTag(XmlResourceParser parser, String parent) {
+ super("Illegal end tag " + parser.getName() + " in " + parent, parser);
+ }
+ }
+
+ @SuppressWarnings("serial")
+ private static class NonEmptyTag extends ParseException {
+ public NonEmptyTag(String tag, XmlResourceParser parser) {
+ super(tag + " must be empty tag", parser);
+ }
+ }
+
+ private static void debugEnterMethod(String title, boolean skip) {
+ Log.d(TAG, title + ": enter" + (skip ? " skip" : ""));
+ }
+
+ private static void debugLeaveMethod(String title, boolean skip) {
+ Log.d(TAG, title + ": leave" + (skip ? " skip" : ""));
+ }
+
+ private static void debugStartTag(String title, String tag, boolean skip) {
+ Log.d(TAG, title + ": <" + tag + ">" + (skip ? " skip" : ""));
+ }
+
+ private static void debugEndTag(String title, String tag, boolean skip) {
+ Log.d(TAG, title + ": </" + tag + ">" + (skip ? " skip" : ""));
+ }
+ }