AndroidStudioエラーメッセージ(java)

カメラアプリを起動しようとした所エミュレーター上にUnfortunately.（アプリ名）has stopped というエラーが出ます logcatには java.lang.RuntimeException: Fail to connect to camera serviceこのように出ます

ソースは２つ載せておきます。

package sample.android.camera01;

        import android.app.Activity;
        import android.os.Bundle;
        import android.view.Window;
        import android.view.WindowManager;
        import android.widget.LinearLayout;

public class SampleCamera01 extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
        requestWindowFeature(Window.FEATURE_NO_TITLE);

        LinearLayout l = new LinearLayout(this);
        l.addView(new SampleView(this));
        setContentView(l);
    }
}

package sample.android.camera01;



        import java.io.IOException;

        import android.content.Context;
        import android.hardware.Camera;
        import android.view.SurfaceHolder;
        import android.view.SurfaceHolder.Callback;
        import android.view.SurfaceView;

public class SampleView extends SurfaceView implements Callback {
    private Camera camera;

    public SampleView(Context context) {
        super(context);
        SurfaceHolder holder = getHolder();
        holder.addCallback(this);
        holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }

    @Override
    public void surfaceCreated(SurfaceHolder holder) {
        try {
            camera = Camera.open();
            camera.setPreviewDisplay(holder);
        } catch(IOException e) {
        }
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int f, int w, int h) {
        Camera.Parameters p = camera.getParameters();
        p.setPreviewSize(w,h);
        camera.setParameters(p);
        camera.startPreview();
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        camera.stopPreview();
        camera.release();
    }

}

追記

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="sample.android.camera01"
    android:versionCode="1"
    android:versionName="1.0">
    <application  android:label="@string/app_name">
        <activity android:name=".SampleCamera01"
            android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

    </application>
    <uses-sdk android:minSdkVersion="4" />

    <uses-permission android:name="android.permission.CAMERA" />
    <uses-permission android:name="android.permission.WRIGHT_EXTERNAL_STORAGE" />

</manifest>