H2 Trigger doesn't Trigger

Question

I'm trying to create an H2 Trigger which should trigger before an Insert query is executed, because I need to set an ID in an SQL Table, which I need to create first in another table

The table where the insert should happen looks like this:

CREATE TABLE IF NOT EXISTS INGREDIENTS(
ID INT NOT NULL,
Name VARCHAR(50),
ALK INT check (ALK <= 100 and ALK >= 0),
CalPerHundred INT,
PRICE DOUBLE check(PRICE>=0),
FOREIGN KEY (ID) REFERENCES ITEM(ID)
);

Create for the Trigger:

CREATE TRIGGER IF NOT EXISTS ING_TRIGGER
BEFORE INSERT
ON INGREDIENTS
FOR EACH ROW
CALL "Partyplaner.Persistence.Trigger.IngredientsTrigger";

The code for the Trigger:

public class IngredientsTrigger implements Trigger {

    private Logger LOGGER = LoggerFactory.getLogger(IngredientsTrigger.class);

    @Override
    public void init(Connection conn, String schemaName,
                     String triggerName, String tableName, boolean before, int type)
            throws SQLException {
        LOGGER.debug("hello im init");
    }

    @Override
    public void fire(Connection conn, Object[] oldRow, Object[] newRow)throws SQLException {

        LOGGER.debug("hello im fire");
        PreparedStatement pstmt_key;
        try {
            pstmt_key = conn.prepareStatement("INSERT INTO ITEM () VALUES ()");
        } catch (SQLException e) {
            throw e;
        }
        pstmt_key.executeUpdate();
        ResultSet generatedKeys = pstmt_key.getGeneratedKeys();
        generatedKeys.next();

        int id = generatedKeys.getInt(1);

        generatedKeys.close();

        newRow[0]=id;



    }

    @Override
    public void close() throws SQLException {}

    @Override
    public void remove() throws SQLException {}
}

I can see the Trigger in the H2 WebInterface, but when I'm trying to Insert a Ingredient, I get an SQL error which says NULL is not allowed for ID; but that's exactly what the Trigger should do? I only see the init log message from the Trigger, so I'm relatively sure it doesn't get called, I checked the classpath in the create file like 5 Times, even let it print with Trigger.class.getName().

I'm using Maven and Spring, could it be that the Classpath has to be something else because of it?

Answer 1

Ok, the answer was pretty simple, i had to delete the NOT NULL Annotation from the Table now everything is working fine.