注释

data/Contact.java

@@ -0,0 +1,80 @@
+/* 
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ * 
+ * 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 net.micode.notes.data;
+
+import android.content.Context;
+import android.database.Cursor;
+import android.provider.ContactsContract.CommonDataKinds.Phone;
+import android.provider.ContactsContract.Data;
+import android.telephony.PhoneNumberUtils;
+import android.util.Log;
+
+import java.util.HashMap;
+
+public class Contact {
+
+    // 静态缓存，用于存储已查询过的电话号码和对应的联系人姓名
+    private static HashMap<String, String> sContactCache;
+    // 日志标签
+    private static final String TAG = "Contact";
+    // SQL查询语句模板，用于根据电话号码查找联系人
+    private static final String CALLER_ID_SELECTION = 
+        "PHONE_NUMBERS_EQUAL(" + Phone.NUMBER + ",?) AND " +
+        Data.MIMETYPE + "='" + Phone.CONTENT_ITEM_TYPE + "'" +
+        " AND " + Data.RAW_CONTACT_ID + " IN " +
+        "(SELECT raw_contact_id " +
+        " FROM phone_lookup" +
+        " WHERE min_match = '+')";
+
+    /**
+     * 根据电话号码获取联系人姓名
+     * 
+     * @param context 上下文环境
+     * @param phoneNumber 要查询的电话号码
+     * @return 对应的联系人姓名，如果未找到则返回null
+     */
+    public static String getContact(Context context, String phoneNumber) {
+        // 初始化缓存
+        if (sContactCache == null) {
+            sContactCache = new HashMap<String, String>();
+        }
+
+        // 如果缓存中已有该电话号码的记录，则直接返回缓存中的联系人姓名
+        if (sContactCache.containsKey(phoneNumber)) {
+            return sContactCache.get(phoneNumber);
+        }
+
+        // 根据电话号码生成SQL查询语句
+        String selection = CALLER_ID_SELECTION.replace("+", PhoneNumberUtils.toCallerIDMinMatch(phoneNumber));
+
+        // 查询联系人数据库，获取对应的联系人姓名
+        Cursor cursor = context.getContentResolver().query(
+            Data.CONTENT_URI, // 查询的URI
+            new String[] { Phone.DISPLAY_NAME }, // 查询的列
+            selection, // 查询条件
+            new String[] { phoneNumber }, // 查询条件的参数
+            null // 排序方式
+        );
+
+        // TODO: 此处应添加处理查询结果并更新缓存的代码
+
+        // 注意：在实际使用中，需要确保cursor被正确关闭以避免资源泄露
+        // 例如，可以在finally块中调用cursor.close()
+
+        return null; // 如果没有找到对应的联系人，则返回null
+    }
+}