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diff --git a/java/src/com/android/inputmethod/event/EventInterpreter.java b/java/src/com/android/inputmethod/event/EventInterpreter.java
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+++ b/java/src/com/android/inputmethod/event/EventInterpreter.java
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+/*
+ * Copyright (C) 2012 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.event;
+
+import android.util.SparseArray;
+import android.view.KeyEvent;
+
+import com.android.inputmethod.latin.Constants;
+import com.android.inputmethod.latin.LatinIME;
+
+/**
+ * This class implements the logic between receiving events and generating code points.
+ *
+ * Event sources are multiple. It may be a hardware keyboard, a D-PAD, a software keyboard,
+ * or any exotic input source.
+ * This class will orchestrate the decoding chain that starts with an event and ends up with
+ * a stream of code points + decoding state.
+ */
+public class EventInterpreter {
+    // TODO: Implement an object pool for events, as we'll create a lot of them
+    // TODO: Create a combiner
+    // TODO: Create an object type to represent input material + visual feedback + decoding state
+    // TODO: Create an interface to call back to Latin IME through the above object
+
+    final EventDecoderSpec mDecoderSpec;
+    final SparseArray<HardwareEventDecoder> mHardwareEventDecoders;
+    final SoftwareEventDecoder mSoftwareEventDecoder;
+    final LatinIME mLatinIme;
+
+    /**
+     * Create a default interpreter.
+     *
+     * This creates a default interpreter that does nothing. A default interpreter should normally
+     * only be used for fallback purposes, when we really don't know what we want to do with input.
+     *
+     * @param latinIme a reference to the ime.
+     */
+    public EventInterpreter(final LatinIME latinIme) {
+        this(null, latinIme);
+    }
+
+    /**
+     * Create an event interpreter according to a specification.
+     *
+     * The specification contains information about what to do with events. Typically, it will
+     * contain information about the type of keyboards - for example, if hardware keyboard(s) is/are
+     * attached, their type will be included here so that the decoder knows what to do with each
+     * keypress (a 10-key keyboard is not handled like a qwerty-ish keyboard).
+     * It also contains information for combining characters. For example, if the input language
+     * is Japanese, the specification will typically request kana conversion.
+     * Also note that the specification can be null. This means that we need to create a default
+     * interpreter that does no specific combining, and assumes the most common cases.
+     *
+     * @param specification the specification for event interpretation. null for default.
+     * @param latinIme a reference to the ime.
+     */
+    public EventInterpreter(final EventDecoderSpec specification, final LatinIME latinIme) {
+        mDecoderSpec = null != specification ? specification : new EventDecoderSpec();
+        // For both, we expect to have only one decoder in almost all cases, hence the default
+        // capacity of 1.
+        mHardwareEventDecoders = new SparseArray<HardwareEventDecoder>(1);
+        mSoftwareEventDecoder = new SoftwareKeyboardEventDecoder();
+        mLatinIme = latinIme;
+    }
+
+    // Helper method to decode a hardware key event into a generic event, and execute any
+    // necessary action.
+    public boolean onHardwareKeyEvent(final KeyEvent hardwareKeyEvent) {
+        final Event decodedEvent = getHardwareKeyEventDecoder(hardwareKeyEvent.getDeviceId())
+                .decodeHardwareKey(hardwareKeyEvent);
+        return onEvent(decodedEvent);
+    }
+
+    public boolean onSoftwareEvent() {
+        final Event decodedEvent = getSoftwareEventDecoder().decodeSoftwareEvent();
+        return onEvent(decodedEvent);
+    }
+
+    private HardwareEventDecoder getHardwareKeyEventDecoder(final int deviceId) {
+        final HardwareEventDecoder decoder = mHardwareEventDecoders.get(deviceId);
+        if (null != decoder) return decoder;
+        // TODO: create the decoder according to the specification
+        final HardwareEventDecoder newDecoder = new HardwareKeyboardEventDecoder(deviceId);
+        mHardwareEventDecoders.put(deviceId, newDecoder);
+        return newDecoder;
+    }
+
+    private SoftwareEventDecoder getSoftwareEventDecoder() {
+        // Within the context of Latin IME, since we never present several software interfaces
+        // at the time, we should never need multiple software event decoders at a time.
+        return mSoftwareEventDecoder;
+    }
+
+    private boolean onEvent(final Event event) {
+        if (event.isCommittable()) {
+            mLatinIme.onCodeInput(event.getCodePoint(),
+                    Constants.EXTERNAL_KEYBOARD_COORDINATE, Constants.EXTERNAL_KEYBOARD_COORDINATE);
+            return true;
+        }
+        // TODO: Classify the event - input or non-input (see design doc)
+        // TODO: IF action event
+        //          Send decoded action back to LatinIME
+        //       ELSE
+        //          Send input event to the combiner
+        //          Get back new input material + visual feedback + combiner state
+        //          Route the event to Latin IME
+        //       ENDIF
+        return false;
+    }
+}