Andriod SQLite Warn : I have some strange warn with SQLite.
<br>What does it mean ?

11-30 13:05:23.653 9964-9964/com.hikari.dev.servermonitor D/SQLiteDatabase: Open database
    java.lang.Throwable: stacktrace
        at android.database.sqlite.SQLiteDatabase.open(SQLiteDatabase.java:815)
        at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:714)
        at android.app.ContextImpl.openOrCreateDatabase(ContextImpl.java:578)
        at android.content.ContextWrapper.openOrCreateDatabase(ContextWrapper.java:269)
        at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:223)
        at android.database.sqlite.SQLiteOpenHelper.getReadableDatabase(SQLiteOpenHelper.java:187)
     -> at com.hikari.dev.servermonitor.main.onClick(main.java:40)
        at android.view.View.performClick(View.java:5269)
        at android.view.View$PerformClick.run(View.java:21556)
        at android.os.Handler.handleCallback(Handler.java:815)
        at android.os.Handler.dispatchMessage(Handler.java:104)
        at android.os.Looper.loop(Looper.java:207)
        at android.app.ActivityThread.main(ActivityThread.java:5769)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:789)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:679)

database_helper.java (singleton) 

    package com.hikari.dev.servermonitor;

    import android.content.Context;
    import android.database.sqlite.SQLiteDatabase;
    import android.database.sqlite.SQLiteOpenHelper;

    public class database_helper extends SQLiteOpenHelper
    {
        // Database
        public static final int DATABASE_VERSION = 1;
        public static final String DATABASE_NAME = "ServerMonitorDatabase";
        public static final String TABLE_SERVERS = "servers";

    //Servers
    public static final String SERVER_ID = "_id";
    public static final String SERVER_NAME = "name";
    public static final String SERVER_MONITORING_STATUS = "monitoring_status";
    public static final String SERVER_IP = "ip";
    public static final String SERVER_PORT = "port";

    //Singleton
    private static database_helper instance;

    public static database_helper getInstance(Context context)
    {
        if(instance == null)
            instance = new database_helper(context.getApplicationContext());
        return instance;
    }

    @Override
    public void onCreate(SQLiteDatabase sqLiteDatabase)
    {
        sqLiteDatabase.execSQL("create table " + TABLE_SERVERS + "(" + SERVER_ID
                + " integer primary key," + SERVER_NAME  + " text," + SERVER_MONITORING_STATUS
                + " integer," + SERVER_IP + " text," + SERVER_PORT + " integer)");
    }

    @Override
    public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1)
    {
        sqLiteDatabase.execSQL("drop table if exists" + TABLE_SERVERS);

        onCreate(sqLiteDatabase);
    }

    private database_helper(Context context)
    {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }


    }


main.java

    (40)    SQLiteDatabase database = database_helper.getInstance(this).getReadableDatabase();