[Demonstration 1]

[Buggy Method]
public boolean isModified() {
    for (ModelRow r : set.allRows) {
        if (r.isModified()) {
            return true;
        }
    }
    return false;
}

[Buggy Hunk]
if(r.isModified()) {

[Patch]
if(r != null && r.isModified()) {

[Demonstration 2]

[Buggy Method]
@Override
public boolean addAll(Collection<? extends T> collection) {
    boolean result = false;
    int position = underlyingList.size();
    if (collection != null) {
        result = underlyingList.addAll(collection);
    }
    if (result) {
        onItemRangeInserted(position, collection.size());
    }
    return result;
}

[Buggy Hunk]
int position = underlyingList.size();

[Patch]
int position = underlyingList.size() - 1;

[Demonstration 3]

[Buggy Method]
public boolean isItem(String barcode) {
    SQLiteDatabase db = this.getWritableDatabase();
    cursor = db.query(TABLE_NAME, new String[] { BARCODE, BC_TYPE }, BARCODE + "=?", new String[] { barcode }, null, null, sortOrder);
    cursor.moveToFirst();
    this.close();
    return cursor.getString(cursor.getColumnIndex(BC_TYPE)).equals("item");
}

[Buggy Hunk]
cursor = db.query(

[Patch]
Cursor cursor = db.query(