diff --git a/api/current.xml b/api/current.xml
index 4ba4be0749e37..7806c244ecde5 100644
--- a/api/current.xml
+++ b/api/current.xml
@@ -237414,6 +237414,19 @@
 >
 <implements name="android.os.Parcelable">
 </implements>
+<method name="containsExtraValueKey"
+ return="boolean"
+ abstract="false"
+ native="false"
+ synchronized="false"
+ static="false"
+ final="false"
+ deprecated="not deprecated"
+ visibility="public"
+>
+<parameter name="s" type="java.lang.String">
+</parameter>
+</method>
 <method name="describeContents"
  return="int"
  abstract="false"
@@ -237436,6 +237449,19 @@
  visibility="public"
 >
 </method>
+<method name="getExtraValueOf"
+ return="java.lang.String"
+ abstract="false"
+ native="false"
+ synchronized="false"
+ static="false"
+ final="false"
+ deprecated="not deprecated"
+ visibility="public"
+>
+<parameter name="s" type="java.lang.String">
+</parameter>
+</method>
 <method name="getIconResId"
  return="int"
  abstract="false"
diff --git a/core/java/android/view/inputmethod/InputMethodSubtype.java b/core/java/android/view/inputmethod/InputMethodSubtype.java
index 0a9386d8a81ef..25f2229936aa6 100644
--- a/core/java/android/view/inputmethod/InputMethodSubtype.java
+++ b/core/java/android/view/inputmethod/InputMethodSubtype.java
@@ -19,9 +19,11 @@ package android.view.inputmethod;
 import android.content.Context;
 import android.os.Parcel;
 import android.os.Parcelable;
+import android.util.Slog;
 
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
 
@@ -32,12 +34,17 @@ import java.util.List;
  * specified subtype of the designated input method directly.
  */
 public final class InputMethodSubtype implements Parcelable {
+    private static final String TAG = InputMethodSubtype.class.getSimpleName();
+    private static final String EXTRA_VALUE_PAIR_SEPARATOR = ",";
+    private static final String EXTRA_VALUE_KEY_VALUE_SEPARATOR = "=";
+
     private final int mSubtypeNameResId;
     private final int mSubtypeIconResId;
     private final String mSubtypeLocale;
     private final String mSubtypeMode;
     private final String mSubtypeExtraValue;
     private final int mSubtypeHashCode;
+    private HashMap<String, String> mExtraValueHashMapCache;
 
     /**
      * Constructor
@@ -106,6 +113,46 @@ public final class InputMethodSubtype implements Parcelable {
         return mSubtypeExtraValue;
     }
 
+    private HashMap<String, String> getExtraValueHashMap() {
+        if (mExtraValueHashMapCache == null) {
+            mExtraValueHashMapCache = new HashMap<String, String>();
+            final String[] pairs = mSubtypeExtraValue.split(EXTRA_VALUE_PAIR_SEPARATOR);
+            final int N = pairs.length;
+            for (int i = 0; i < N; ++i) {
+                final String[] pair = pairs[i].split(EXTRA_VALUE_KEY_VALUE_SEPARATOR);
+                if (pair.length == 1) {
+                    mExtraValueHashMapCache.put(pair[0], null);
+                } else if (pair.length > 1) {
+                    if (pair.length > 2) {
+                        Slog.w(TAG, "ExtraValue has two or more '='s");
+                    }
+                    mExtraValueHashMapCache.put(pair[0], pair[1]);
+                }
+            }
+        }
+        return mExtraValueHashMapCache;
+    }
+
+    /**
+     * The string of ExtraValue in subtype should be defined as follows:
+     * example: key0,key1=value1,key2,key3,key4=value4
+     * @param key the key of extra value
+     * @return the subtype contains specified the extra value
+     */
+    public boolean containsExtraValueKey(String key) {
+        return getExtraValueHashMap().containsKey(key);
+    }
+
+    /**
+     * The string of ExtraValue in subtype should be defined as follows:
+     * example: key0,key1=value1,key2,key3,key4=value4
+     * @param key the key of extra value
+     * @return the value of the specified key
+     */
+    public String getExtraValueOf(String key) {
+        return getExtraValueHashMap().get(key);
+    }
+
     @Override
     public int hashCode() {
         return mSubtypeHashCode;
diff --git a/services/java/com/android/server/InputMethodManagerService.java b/services/java/com/android/server/InputMethodManagerService.java
index d25b9c8148db4..ba0f31b92250a 100644
--- a/services/java/com/android/server/InputMethodManagerService.java
+++ b/services/java/com/android/server/InputMethodManagerService.java
@@ -1949,14 +1949,7 @@ public class InputMethodManagerService extends IInputMethodManager.Stub
 
     private boolean canAddToLastInputMethod(InputMethodSubtype subtype) {
         if (subtype == null) return true;
-        String[] extraValues = subtype.getExtraValue().split(",");
-        final int N = extraValues.length;
-        for (int i = 0; i < N; ++i) {
-            if (SUBTYPE_EXTRAVALUE_EXCLUDE_FROM_LAST_IME.equals(extraValues[i])) {
-                return false;
-            }
-        }
-        return true;
+        return subtype.containsExtraValueKey(SUBTYPE_EXTRAVALUE_EXCLUDE_FROM_LAST_IME);
     }
 
     private void saveCurrentInputMethodAndSubtypeToHistory() {