Have a pool of dictionaries to check spelling.

The dictionaries and proximities are not thread-safe. In order to
be able to check spelling in parallel, make a dictionary pool to
call upon when a spelling check is necessary.

Bug: 5156851
Change-Id: Ie3796164187dd7b7abf5ccd5d014073d43d74408

1 files changed, 55 insertions, 0 deletions

diff --git a/java/src/com/android/inputmethod/latin/spellcheck/DictionaryPool.java b/java/src/com/android/inputmethod/latin/spellcheck/DictionaryPool.java
new file mode 100644
index 000000000..dfbfcc7f6
--- /dev/null
+++ b/java/src/com/android/inputmethod/latin/spellcheck/DictionaryPool.java
@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2011 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.inputmethod.latin.spellcheck;
+
+import android.content.Context;
+
+import java.util.Locale;
+import java.util.concurrent.LinkedBlockingQueue;
+
+/**
+ * A blocking queue that creates dictionaries up to a certain limit as necessary.
+ */
+public class DictionaryPool extends LinkedBlockingQueue<DictAndProximity> {
+    private final AndroidSpellCheckerService mService;
+    private final int mMaxSize;
+    private final Locale mLocale;
+    private int mSize = 0;
+
+    public DictionaryPool(final int maxSize, final AndroidSpellCheckerService service,
+            final Locale locale) {
+        super();
+        mMaxSize = maxSize;
+        mService = service;
+        mLocale = locale;
+    }
+
+    @Override
+    public DictAndProximity take() throws InterruptedException {
+        final DictAndProximity dict = poll();
+        if (null != dict) return dict;
+        synchronized(this) {
+            if (mSize >= mMaxSize) {
+                // Our pool is already full. Wait until some dictionary is ready.
+                return super.take();
+            } else {
+                ++mSize;
+                return mService.createDictAndProximity(mLocale);
+            }
+        }
+    }
+}