Hibernate Exceptions Errors and Causes

By -
The following section will list the general exception that we get while dealing with hibernate.



org.hibernate.ObjectDeletedException:deleted object would be re-saved by cascade
when we try to delete the child object and don't remove the association, for instance we loaded a parent object with list of child and then we deleted one of the

child object but did not removed the child from the parent.

Example,

Box gotBox =(Box)dao.load(Box.class, box.getBoxId());

List boxitem = new ArrayList(gotBox.getBoxItems());

BoxItem deleteItem = boxitem.get(0);

dao.deletItem(deleteItem.getItemName());

Solution is, remove the transient instance from the parent object(Box) like.
 
gotBox.getBoxItems().remove(deleteItem);

OR use
 
@Cascade(value=org.hibernate.annotations.CascadeType.DELETE_ORPHAN)

on the child object.
-------------------------------------------------------------------------------------------------


No Dialect mapping for JDBC type: -1


We get this exception when trying to execute SQLQuery in hibernate and the query returns columns value that Hibernate not able to identify(map to its own data type, for example MySQL Data type Text.

CREATE TABLE `country`
(`countryId` INT  NOT NULL,`countryName` TEXT  NOT NULL) 
 
If we execute the following 
SQLQuery query = session.createSQLQuery("select * from country");    
countries = query.list(); 
We will get the exception.
The solution is to add scalar to query object.
like,
query.addScalar("countryId", Hibernate.LONG);
query.addScalar("countryName", Hibernate.STRING);   
Without adding Scalars, hibernate uses ResultSetmetaData to resolve the data types.
 
 
 

Comments

  1. Javin @ Tibco RV TutorialJanuary 29, 2011 at 4:59 AM

    Hi dude,

    In case of any database exception e.g. if some record doesn't exists in db ,does hibernate delivers that error till application level or there is any default way of handling that ?

    Thanks
    Javin
    FIX Protocol tutorial

    ReplyDelete

Post a Comment

Popular posts from this blog

Difference between volatile and synchronized

By -
volatile is a field modifier, while synchronized modifies code blocks and methods. So we can specify three variations of a simple accessor using those two keywords: int i1; int geti1() {return i1;} volatile int i2; int geti2() {return i2;} int i3; synchronized int geti3() {return i3;} geti1() accesses the value currently stored in i1 in the current thread . Threads can have local copies of variables, and the data does not have to be the same as the data held in other threads. In particular, another thread may have updated i1 in it's thread, but the value in the current thread could be different from that updated value. In fact Java has the idea of a "main" memory, and this is the memory that holds the current "correct" value for variables. Threads can have their own copy of data for variables, and the thread copy can be different from the "main" memory. So in fact, it is possible for the "main"
Read more

Converting Java Map to String

By -
Java Collections framework, String manipulation etc is something that we often encounter in Development process. For processing collections (like checking null/empty, Intersection, Disjunction) We do have some of the very use full libraries. Some of the Collection related libraries are Apche Commons Collections and Google  Collections(Guava). Problem Use Case This article explains how to convert a Java Map to String(and vice versa) using different libraries and technique. One way is to use StringBuilder(Or String) and loop though the Map and build the String by applying some sort of separator ( for key:value and entry). Here we have to take care of the null value etc. Without Any Library If we want to convert the map to a String with key value separator and also individual entry seperator in the resulting String, we have to write code for that. For a simple Map, we have to iterate though the map, take care of the null values etc. Following is a sample to get String built
Read more

Masking Credit Card number in Java

By -
Sometimes we need to mask crucial information like Credit Card Numbers, CVV numbers etc before storing  or logging the information. This example mask Credit Card Number (Except last 4 Digit) from a Text which contains information along with Credit Card Number. The following example demonstrates how we can easily mask the credit card with Matcher and Pattern Classes. This Sample Code uses Matcher and Pattern. Pattern Used in this sample is not optimized for Credit Card Numbers, this pattern will get any numerical numbers in the String Content.  Based on the Credit Card Type a more efficient and Strict RegEx can be used to mask the Credit Card. /**Mask the Credit card number but last four digit value **/   Pattern PATTERN = Pattern.compile( "[0-9]+" ); String message = content; Matcher matcher = PATTERN.matcher(message); String maskingChar = "*"; StringBuilder finalMask = new StringBuilder(maskingChar);
Read more