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PONull Pointer exception when attempting to update row of sqlite database in android
 

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  1. PONull Pointer exception when attempting to update row of sqlite database in android
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    <p>First off, I have looked at all the similar questions that hours of google and SO searches have displayed. No luck.</p> <p>I have a Database Helper class called PropertiesDatabase which extends SQLiteOpenHelper as follows:</p> <pre><code>private static final class PropertiesDatabase extends SQLiteOpenHelper{ static final int DATABASE_VERSION = 1; private static final String KEY_PROPERTIES_TABLE = "PropertiesTable"; static final String KEY_ID = "_id"; static final String KEY_NAME = "name"; static final String KEY_SIZE = "size"; static final String KEY_PASSWORD = "password"; static final String [] columnsProperties = new String[] { KEY_NAME, KEY_SIZE, KEY_PASSWORD}; private static String CREATE_TABLE; public PropertiesDatabase(Context context) { super(context, KEY_PROPERTIES_TABLE, null, DATABASE_VERSION); } @Override public void onCreate(SQLiteDatabase db) { CREATE_TABLE = "create table " + KEY_PROPERTIES_TABLE + "(" + KEY_ID + " integer primary key autoincrement, " + KEY_NAME + " text not null, " + KEY_SIZE + " integer," + KEY_PASSWORD + " text" + ");"; db.execSQL(CREATE_TABLE); } public void changeName(String oldName, String newName){ SQLiteDatabase db = this.getReadableDatabase(); ContentValues values = new ContentValues(); values.put(KEY_NAME, newName); db.update(KEY_PROPERTIES_TABLE, values, KEY_NAME + "=?", new String[] {oldName}); db.close(); } public void changeSize(String name, int n){ SQLiteDatabase db = this.getReadableDatabase(); ContentValues values = new ContentValues(); values.put(KEY_SIZE, n); db.update(KEY_PROPERTIES_TABLE, values, KEY_NAME + "=?", new String[] {name}); db.close(); } } </code></pre> <p>There are many more methods in the class, but I've included changeName and changeSize because they are almost identical, but the first works and the second throws a null pointer exception. The logcat says that the call </p> <pre><code>db.update(KEY_PROPERTIES_TABLE, values, KEY_NAME + "=?", new String[] {name}); </code></pre> <p>In the changeSize() method is the culprit. I checked using db.isOpen() immediately before that call, and the database is not open. It is open, however, before the update call in changeName().</p> <p>I can't understand why one method works fine and the other doesn't. Any help solving that mystery would be appreciated.</p> <p>Thank you for taking the time to read this.</p> <p><strong>Edit:</strong></p> <p>Here is the relevant logcat info:</p> <pre><code>01-31 13:37:17.315: E/AndroidRuntime(1978): FATAL EXCEPTION: main 01-31 13:37:17.315: E/AndroidRuntime(1978): java.lang.NullPointerException 01-31 13:37:17.315: E/AndroidRuntime(1978): at android.database.sqlite.SQLiteStatement.releaseAndUnlock(SQLiteStatement.java:290) 01-31 13:37:17.315: E/AndroidRuntime(1978): at android.database.sqlite.SQLiteStatement.executeInsert(SQLiteStatement.java:115) 01-31 13:37:17.315: E/AndroidRuntime(1978): at android.database.sqlite.SQLiteDatabase.insertWithOnConflict(SQLiteDatabase.java:1825) 01-31 13:37:17.315: E/AndroidRuntime(1978): at android.database.sqlite.SQLiteDatabase.replace(SQLiteDatabase.java:1744) 01-31 13:37:17.315: E/AndroidRuntime(1978): at com.LN.AppName.DatabaseHandler$PropertiesDatabase.changeSize(DatabaseHandler.java:767) </code></pre> <p>Line 767 is, of course, the call to update.</p> <p>Thanks again!</p>
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    1. This table or related slice is empty.
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    1. USRookatu
    1. USRookatu
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
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      1. PONull Pointer exception when attempting to update row of sqlite database in android
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
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      1. This table or related slice is empty.
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      1. PONull Pointer exception when attempting to update row of sqlite database in android
      1. This table or related slice is empty.
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    1. COcan you check if (String name) is null?
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      1. USwtsang02
    2. COYeah, I checked that and it isn't
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      1. USRookatu
    3. COjust for fun, could you post your LogCat?
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      1. USDavid M
 

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