安卓中 广播 服务 及其简单应用范围的一些总结

1.广播与广播接收者

1.API

静态注册广播接收者

清单文件中配置:

<code class="hljs xml has-numbering"><span class="hljs-tag"><<span class="hljs-title">receiver</span> <span class="hljs-attribute">android:name</span>=<span class="hljs-value">"包名.广播接收者文件"</span> ></span>
<span class="hljs-tag"><<span class="hljs-title">intent-filter</span> <span class="hljs-attribute">android:priority</span>=<span class="hljs-value">"广播拦截的优先级(最大:2147483647)"</span> ></span>
<span class="hljs-tag"><<span class="hljs-title">action</span> <span class="hljs-attribute">android:name</span>=<span class="hljs-value">"广播监听的动作 可以是自定义的或者系统广播"</span> /></span>
<span class="hljs-tag"></<span class="hljs-title">intent-filter</span>></span>
<span class="hljs-tag"></<span class="hljs-title">receiver</span>></span></code>

动态注册广播接收者

1.动态创建一个广播接收者

<code class="hljs axapta has-numbering">        <span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">MyReceiver</span> <span class="hljs-inheritance"><span class="hljs-keyword">extends</span></span> <span class="hljs-title">BroadcastReceiver</span> {</span>
@Override
<span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> onReceive(Context context, Intent intent) {

<span class="hljs-comment">//收到广播后 </span>
<span class="hljs-comment">//1.可以触发某些事件</span>
<span class="hljs-comment">//2.从initen参数中获取广播发送的数据</span>
}
};</code>

2.对广播接收者进行动态注册

<code class="hljs mel has-numbering">    Receiver = new MyReceiver();
<span class="hljs-comment">//设置filter信息</span>
IntentFilter <span class="hljs-keyword">filter</span> = new IntentFilter();
<span class="hljs-keyword">filter</span>.addAction(<span class="hljs-string">"自定义的或者系统广播"</span>);   <span class="hljs-comment">//设置广播监听的动作</span>
<span class="hljs-comment">//注册</span>
registerReceiver(Receiver, <span class="hljs-keyword">filter</span>);</code> <ul class="pre-numbering" style=""><li> </li></ul>

3.取消注册

<code class="hljs fix has-numbering"><span class="hljs-attribute">unregisterReceiver(mReceiver);
mReceiver </span>=<span class="hljs-string"> null;</span></code>

自定义广播发送(通过intent携带数据)

<code class="hljs cs has-numbering">    Intent intent = <span class="hljs-keyword">new</span> Intent();
intent.putExtra(<span class="hljs-string">"键"</span>, 要携带到接收者的信息);
intent.setAction(<span class="hljs-string">"自定义广播"</span>);            <span class="hljs-comment">//设置广播监听的动作</span>
sendBroadcast(intent);</code>

两种广播的区别

静态注册广播接收者在程序的整个运行期间都会监听。

动态注册的广播接收者可以控制在需要的时候开启监听，不需要的时候关闭监听。通常可以将动态注册广播接收者放到一个服务中,服务开启时注册广播，服务关闭时取消注册。

2.例子

常见系统广播

//监听系统启动广播

<code class="hljs xml has-numbering">    <span class="hljs-tag"><<span class="hljs-title">receiver</span> <span class="hljs-attribute">android:name</span>=<span class="hljs-value">".receiver.BootCompleteReceiver"</span> ></span>
<span class="
4000
hljs-tag"><<span class="hljs-title">intent-filter</span>></span>
<span class="hljs-tag"><<span class="hljs-title">action</span> <span class="hljs-attribute">android:name</span>=<span class="hljs-value">"android.intent.action.BOOT_COMPLETED"</span> /></span>
<span class="hljs-tag"></<span class="hljs-title">intent-filter</span>></span>
<span class="hljs-tag"></<span class="hljs-title">receiver</span>></span></code>

//监听短信

<code class="hljs xml has-numbering">       <span class="hljs-tag"><<span class="hljs-title">receiver</span> <span class="hljs-attribute">android:name</span>=<span class="hljs-value">".receiver.SmsReceiver"</span> ></span>
<span class="hljs-tag"><<span class="hljs-title">intent-filter</span> <span class="hljs-attribute">android:priority</span>=<span class="hljs-value">"2147483647"</span> ></span>
<span class="hljs-tag"><<span class="hljs-title">action</span> <span class="hljs-attribute">android:name</span>=<span class="hljs-value">"android.provider.Telephony.SMS_RECEIVED"</span> /></span>
<span class="hljs-tag"></<span class="hljs-title">intent-filter</span>></span>
<span class="hljs-tag"></<span class="hljs-title">receiver</span>></span></code>

//获取管理员权限  MyAdminReceiver需要实现但是不用写内容

<code class="hljs xml has-numbering">    <span class="hljs-tag"><<span class="hljs-title">receiver
</span>            <span class="hljs-attribute">android:name</span>=<span class="hljs-value">".receiver.MyAdminReceiver"</span>
<span class="hljs-attribute">android:description</span>=<span class="hljs-value">"@string/sample_device_admin_description"</span>
<span class="hljs-attribute">android:label</span>=<span class="hljs-value">"@string/sample_device_admin"</span>
<span class="hljs-attribute">android:permission</span>=<span class="hljs-value">"android.permission.BIND_DEVICE_ADMIN"</span> ></span>
<span class="hljs-tag"><<span class="hljs-title">meta-data
</span>                <span class="hljs-attribute">android:name</span>=<span class="hljs-value">"android.app.device_admin"</span>
<span class="hljs-attribute">android:resource</span>=<span class="hljs-value">"@xml/device_admin_sample"</span> /></span>

<span class="hljs-tag"><<span class="hljs-title">intent-filter</span>></span>
<span class="hljs-tag"><<span class="hljs-title">action</span> <span class="hljs-attribute">android:name</span>=<span class="hljs-value">"android.app.action.DEVICE_ADMIN_ENABLED"</span> /></span>
<span class="hljs-tag"></<span class="hljs-title">intent-filter</span>></span>
<span class="hljs-tag"></<span class="hljs-title">receiver</span>></span></code>

//监听创建快捷方式

<code class="hljs xml has-numbering">      <span class="hljs-tag"><<span class="hljs-title">receiver</span> <span class="hljs-attribute">android:name</span>=<span class="hljs-value">".receiver.MyWidget"</span> ></span>
<span class="hljs-tag"><<span class="hljs-title">intent-filter</span>></span>
<span class="hljs-tag"><<span class="hljs-title">action</span> <span class="hljs-attribute">android:name</span>=<span class="hljs-value">"android.appwidget.action.APPWIDGET_UPDATE"</span> /></span>
<span class="hljs-tag"></<span class="hljs-title">intent-filter</span>></span>

<span class="hljs-tag"><<span class="hljs-title">meta-data
</span>                <span class="hljs-attribute">android:name</span>=<span class="hljs-value">"android.appwidget.provider"</span>
<span class="hljs-attribute">android:resource</span>=<span class="hljs-value">"@xml/process_widget_provider"</span> /></span>
<span class="hljs-tag"></<span class="hljs-title">receiver</span>></span></code>

//监听杀死所有进程

<code class="hljs xml has-numbering">       <span class="hljs-tag"><<span class="hljs-title">receiver</span> <span class="hljs-attribute">android:name</span>=<span class="hljs-value">".receiver.KillProcess"</span>></span>
<span class="hljs-tag"><<span class="hljs-title">intent-filter</span>></span>
<span class="hljs-tag"><<span class="hljs-title">action</span> <span class="hljs-attribute">android:name</span>=<span class="hljs-value">"com.example.mobilesafe.KILLALLPROCESS"</span> /></span>
<span class="hljs-tag"></<span class="hljs-title">intent-filter</span>></span>
<span class="hljs-tag"></<span class="hljs-title">receiver</span>></span></code> <ul class="pre-numbering" style=""><li> </li></ul>

动态注册广播接收者(一般在服务中动态注册 重要)

适用情况: 广播接收者监听事件变化，有变化后就返回给服务，服务通过返回Bind或者写SharePrecefence等方法传出数据。

具体运用举例：

1.开启电话监听，监听来电去电 ，例如 黑名单，归属地查询等

2.程序加锁 ，监听当前栈顶程序是否被加锁

3.实时定位 ，不断读取当前定位信息

4.锁屏事件 ，监听到锁屏后可以做一些清理工作

5.和桌面上的Widget通信

两种注册类型的区别：
静态注册是当程序关闭后，如果有广播发过来，还能启动程序
动态注册的生命周期跟程序的生命周期是一样的，程序关闭后动态注册的广播是不能在接收到广播的

动态注册的优点：在Android的广播机制中，动态注册的优先级高于静态注册的优先级，因此在必要情况下，我们需要动态注册广播接收器。
静态注册的有点：动态注册广播接收器还有一个优点就是当用来注册广播的Activity关闭后，广播也就失效了，同时反映了静态注册广播的一个优势，就是无需担心广播接收器是否关闭，只要设备处于开启状态，广播接收器就能接收。

操作频繁的广播事件，如果只是在清单配置文件配置，是不生效的。需要使用代码注册才能生效；

步骤：

<code class="hljs axapta has-numbering">     例<span class="hljs-number">1</span>:<span class="hljs-comment">// 监听屏幕开关</span>
<span class="hljs-comment">// 1、得到广播接收者的对象</span>
ScreenBroadCastReceiver screenReceiver = <span class="hljs-keyword">new</span> ScreenBroadCastReceiver();
<span class="hljs-comment">// 2、创建一个intentFilter对象</span>
IntentFilter filter = <span class="hljs-keyword">new</span> IntentFilter();
<span class="hljs-comment">// 3、注册接收的事件类型</span>
filter.addAction(<span class="hljs-string">"android.intent.action.SCREEN_ON"</span>);
filter.addAction(<span class="hljs-string">"android.intent.action.SCREEN_OFF"</span>);
<span class="hljs-comment">// 4、注册广播接收者</span>
<span class="hljs-keyword">this</span>.registerReceiver(screenReceiver, filter);

例<span class="hljs-number">2.</span><span class="hljs-comment">// 注册监听去电的广播</span>
mReceiver = <span class="hljs-keyword">new</span> OutCallReceiver();
IntentFilter filter = <span class="hljs-keyword">new</span> IntentFilter();
filter.addAction(Intent.ACTION_NEW_OUTGOING_CALL);
registerReceiver(mReceiver, filter);

以上两例需要我们自己实现广播接收者,下面这个例子中系统为我们实现了回调方法

例<span class="hljs-number">3.</span> <span class="hljs-comment">//来电话</span>
mListener = <span class="hljs-keyword">new</span> MyPhoneStateListener();
mTM.listen(mListener, PhoneStateListener.LISTEN_CALL_STATE);<span class="hljs-comment">// 监听来电状态</span>
<span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">MyPhoneStateListener</span> <span class="hljs-inheritance"><span class="hljs-keyword">extends</span></span> <span class="hljs-title">PhoneStateListener</span> {</span>
@Override
<span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> onCallStateChanged(<span class="hljs-keyword">int</span> state, String incomingNumber) {
<span class="hljs-keyword">switch</span> (state) {
<span class="hljs-keyword">case</span> TelephonyManager.CALL_STATE_RINGING:<span class="hljs-comment">// 电话玲响</span>

<span class="hljs-keyword">break</span>;
<span class="hljs-keyword">case</span> TelephonyManager.CALL_STATE_IDLE:<span class="hljs-comment">// 通话结束</span>

<span class="hljs-keyword">break</span>;
<span class="hljs-keyword">default</span>:
<span class="hljs-keyword">break</span>;
}
<span class="hljs-keyword">super</span>.onCallStateChanged(state, incomingNumber);
}
}

例<span class="hljs-number">4.</span><span class="hljs-comment">//设置快捷方式</span>

Intent intent = <span class="hljs-keyword">new</span> Intent(
<span class="hljs-string">"com.android.launcher.action.INSTALL_SHORTCUT"</span>);

<span class="hljs-comment">// 设置快捷方式的图标</span>
intent.putExtra(Intent.EXTRA_SHORTCUT_ICON, BitmapFactory
.decodeResource(getResources(), R.drawable.home_tools));

<span class="hljs-comment">// 设置快捷方式名称</span>
intent.putExtra(Intent.EXTRA_SHORTCUT_NAME, <span class="hljs-string">"黑马小卫士"</span>);

<span class="hljs-comment">//不允许重复</span>
intent.putExtra(<span class="hljs-string">"duplicate"</span>, <span class="hljs-keyword">false</span>);

<span class="hljs-comment">// 动作,跳转主页面</span>
Intent actionIntent = <span class="hljs-keyword">new</span> Intent();
actionIntent.setClass(<span class="hljs-keyword">this</span>,MainActivity.class);
<span class="hljs-comment">//actionIntent.setAction("com.example.mobilesafe.MAIN");// 通过action启动主页面,需要在清单文件配置action</span>
<span class="hljs-comment">//actionIntent.addCategory(Intent.CATEGORY_DEFAULT);// 必须配置categroy</span>
intent.putExtra(Intent.EXTRA_SHORTCUT_INTENT, actionIntent);

<span class="hljs-comment">// 发送广播</span>
sendBroadcast(intent);</code>

2.服务

2.1 API

注册一个服务

<code class="hljs java has-numbering">清单文件
<service android:name=<span class="hljs-string">".service.MyService"</span> />

<span class="hljs-keyword">public</span> <span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">MyService</span> <span class="hljs-keyword">extends</span> <span class="hljs-title">Service</span> {</span>

<span class="hljs-annotation">@Override</span>
<span class="hljs-keyword">public</span> IBinder <span class="hljs-title">onBind</span>(Intent intent) {

<span class="hljs-keyword">return</span> <span class="hljs-keyword">null</span>;
}

<span class="hljs-comment">//创建服务的时候调用</span>
<span class="hljs-annotation">@Override</span>
<span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">onCreate</span>() {
System.out.println(<span class="hljs-string">"*****onCreate******"</span>);
<span class="hljs-keyword">super</span>.onCreate();
}

<span class="hljs-comment">//启动server    每次start都会调用一次</span>
<span class="hljs-annotation">@Override</span>
<span class="hljs-keyword">public</span> <span class="hljs-keyword">int</span> <span class="hljs-title">onStartCommand</span>(Intent intent, <span class="hljs-keyword">int</span> flags, <span class="hljs-keyword">int</span> startId) {
System.out.println(<span class="hljs-string">"*****onStartCommand******"</span>);
<span class="hljs-keyword">return</span> <span class="hljs-keyword">super</span>.onStartCommand(intent, flags, startId);
}

<span class="hljs-comment">//手动停止程序后会终止服务，会调用onDestroy()方法</span>
<span class="hljs-annotation">@Override</span>
<span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">onDestroy</span>() {
System.out.println(<span class="hljs-string">"*****onDestroy******"</span>);
<span class="hljs-keyword">super</span>.onDestroy();
}
}</code>

开启一个服务

<code class="hljs actionscript has-numbering">    <span class="hljs-number">1.</span>启动
<span class="hljs-comment">//使用Intent</span>
Intent intent = <span class="hljs-keyword">new</span> Intent(当前Activity.<span class="hljs-keyword">this</span>, MyService.<span class="hljs-keyword">class</span>);
startService(intent);
stopService(intent);

<span class="hljs-number">2.</span>使用bind让其他组件获取服务提供的数据
<span class="hljs-comment">//使用Intent</span>
Intent intent = <span class=
c437
"hljs-keyword">new</span> Intent(当前Activity.<span class="hljs-keyword">this</span>, MyService.<span class="hljs-keyword">class</span>);
bindService(intent, conn, BIND_AUTO_CREATE);
unbindService(conn);</code><ul class="pre-numbering" style=""><li> </li></ul>

注意事项

bindService绑定服务、unBindService解除绑定的服务；
服务是在被绑定的时候被创建，调用oncreate、onbind方法；
服务只能被绑定一次；
服务只能被解除一次，接触绑定的时候调用onUnbind、onDestrory方法，如果多次解除绑定会抛出异常；

推荐的方式(启用顺序)：

1.startService：开启并创建一个服务，服务长期运行在后台；
2.bindService:绑定服务，可以调用服务里面的方法；
3.unBindService：解除服务，停止服务里面的方法；
4.stopService：停止服务，销毁服务对象；

获取服务中的数据(与服务通信)

<code class="hljs axapta has-numbering">MyService中

<span class="hljs-comment">//这个函数用于返回数据</span>
<span class="hljs-keyword">public</span> IBinder onBind(Intent intent)
{
<span class="hljs-keyword">return</span> <span class="hljs-keyword">new</span> MyBind();     <span class="hljs-comment">//返回到前台的对象，包含要执行的service中的方法</span>
}

<span class="hljs-comment">//继承Binder类，这是因为要返回一个实现IBinder类型接口的</span>
<span class="hljs-keyword">public</span> <span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">MyBind</span> <span class="hljs-inheritance"><span class="hljs-keyword">extends</span></span> <span class="hljs-title">Binder</span>
{</span>
<span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> callPaly() {
paly();
}
}

客户端

<span class="hljs-comment">//绑定服务</span>
bindService(intent, <span class="hljs-keyword">new</span> MyServiceConnection(), BIND_AUTO_CREATE);

<span class="hljs-comment">//获取服务返回的数据</span>
<span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">MyServiceConnection</span> <span class="hljs-inheritance"><span class="hljs-keyword">implements</span></span> <span class="hljs-title">ServiceConnection</span>
{</span>

@Override
<span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> onServiceConnected(ComponentName name, IBinder service) {
<span class="hljs-comment">//返回服务中包含要调用方法的类</span>
serverRet = (MyBind) service;
}

@Override
<span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> onServiceDisconnected(ComponentName name) {
}</code>

aidl 获取其他进程服务的信息

3.内容提供者

3.1API

1.内容解释者

作用: 用来解析内容观察者提供的数据库信息

<code class="hljs axapta has-numbering">ContentResolver contentResolver = getContentResolver();
<span class="hljs-comment">//getContentResolver();是上下文中携带的方法，用于处理内容提供者提供的访问方式。</span>

寻找哪个内容提供者需要用通过uri，uri路径分文 <span class="hljs-string">"主机名"</span>+<span class="hljs-string">"具体要操作的数据"</span>   其中<span class="hljs-string">"主机名"</span>在提供数据库程序的清单文件中定义，<span class="hljs-string">"具体要操作的数据"</span>在这个程序的源码中(一般文件名有provide字样),
我们可以通过查找<span class="hljs-string">"UriMatcher"</span>函数搜索相关的信息。

Uri uri = Uri.parse(<span class="hljs-string">"content://.../"</span>);    <span class="hljs-comment">//指定查询哪个应用下数据库的哪个表</span>

Cursor cursor = contentResolver.query(uri, ... ...);

<span class="hljs-number">2.</span>内容观察者

<span class="hljs-comment">//注册内容观察者</span>
getContentResolver().registerContentObserver(uri, <span class="hljs-keyword">true</span>, <span class="hljs-keyword">new</span> MyObeserver(<span class="hljs-keyword">new</span> Handler()));

<span class="hljs-comment">//收到通知后回调其中的方法</span>
<span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">MyObeserver</span> <span class="hljs-inheritance"><span class="hljs-keyword">extends</span></span> <span class="hljs-title">ContentObserver</span>
{</span>
<span class="hljs-keyword">public</span> MyObeserver(Handler handler) {
<span class="hljs-keyword">super</span>(handler);
}
<span class="hljs-comment">//发现监视路径下的数据库发生变化就会调用此方法         </span>
@Override
<span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> onChange(<span class="hljs-keyword">boolean</span> selfChange) {
<span class="hljs-keyword">super</span>.onChange(selfChange);
}
}

<span class="hljs-comment">//在数据库操作中发出信号，通知观察者</span>

<span class="hljs-comment">// 通知观察者,数据发生变化了</span>
Context.getContentResolver().notifyChange(Uri.parse(<span class="hljs-string">"content://..."</span>),<span class="hljs-keyword">null</span>);</code> <ul class="pre-numbering" style=""><li>32</li></ul>

3.2应用场合举例

1.查询联系人数据库

2.查询短信数据库

3.音乐文件

自定义的数据库我们直接使用SQLiteOpenHelper进行查询

4.意图 的一些应用场合和分类

隐式意图

开启其他应用

<code class="hljs java has-numbering">    安装程序
<span class="hljs-javadoc">/**
* 使用隐式题图安装指定路径下的apk
*<span class="hljs-javadoctag"> @param</span> path
*/</span>
<span class="hljs-keyword">private</span> <span class="hljs-keyword">void</span> <span class="hljs-title">installApk</span>(String path)
{
File file = <span class="hljs-keyword">new</span> File(path);
Intent intent = <span class="hljs-keyword">new</span> Intent();
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.setAction(android.content.Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(file),<span class="hljs-string">"application/vnd.android.package-archive"</span>);
<span class="hljs-comment">//startActivity(intent);</span>
startActivityForResult(intent, <span class="hljs-number">0</span>);
}

卸载程序
<span class="hljs-javadoc">/**
* 卸载应用
*/</span>
<span class="hljs-keyword">private</span> <span class="hljs-keyword">void</span> <span class="hljs-title">uninstall</span>(String packageName) {
<span class="hljs-comment">// 跳转到卸载页面</span>
Intent intent = <span class="hljs-keyword">new</span> Intent(Intent.ACTION_VIEW);
intent.addCategory(Intent.CATEGORY_DEFAULT);
intent.setData(Uri.parse(<span class="hljs-string">"package:"</span> + packageName));
startActivityForResult(intent, <span class="hljs-number">0</span>);
}

清理缓存
<span class="hljs-comment">// 清理单个文件缓存</span>
<span class="hljs-comment">// 跳转到系统设置页面</span>
Intent intent = <span class="hljs-keyword">new</span> Intent();
intent.setAction(<span class="hljs-string">"android.settings.APPLICATION_DETAILS_SETTINGS"</span>);
intent.setData(Uri.parse(<span class="hljs-string">"package:"</span> + info.packageName));
intent.addCategory(Intent.CATEGORY_DEFAULT);
startActivity(intent);

打电话

Intent intent = <span class="hljs-keyword">new</span> Intent(Intent.ACTION_DIAL);
intent.setAction(Intent.ACTION_DIAL);
intent.setData(Uri.parse(<span class="hljs-string">"tel:"</span>+number));
startActivity(intent);</code>

显式意图

...

发送广播

例子见第一章

开启服务

例子见第二章

带返回值的开启新的Activity

1.A页面跳转到B:

<code class="hljs actionscript has-numbering">Intent intent = <span class="hljs-keyword">new</span> Intent(AActivity.<span class="hljs-keyword">this</span>, BActivity.<span class="hljs-keyword">class</span>);

<span class="hljs-comment">//  如果需要返回数据，用此方法发送intent    第二个参数为发送码</span>
startActivityForResult(intent, <span class="hljs-number">2</span>);</code>

2.B页面发送数据给A，B页面关闭:

<code class="hljs r has-numbering">Intent intent = new Intent();
intent.putExtra(<span class="hljs-string">"..."</span>, <span class="hljs-keyword">...</span>);
setResult(<span class="hljs-number">2</span>, intent);

finish();</code>

3.A页面接收B传来的数据:

<code class="hljs r has-numbering">    @Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {

<span class="hljs-keyword">if</span>(resultCode == <span class="hljs-number">1</span>)
{
<span class="hljs-keyword">...</span>
}<span class="hljs-keyword">else</span> <span class="hljs-keyword">if</span>(resultCode == <span class="hljs-number">2</span>){
<span class="hljs-keyword">...</span>
}

super.onActivityResult(requestCode, resultCode, data);
}</code>