Software Engineering

Problem I had two objects Contacts and Groups having many-to-many association. A Contact can belong to multiple Groups and a Group can contain multiple Contacts. My objective was to return a set of Contacts along with the Groups they were associated with. But if the Contacts-Groups association is set to Lazy load then the above exception will be thrown. Solution 1. FetchType can be set to EAGER and everything will work fine, the Groups will be loaded; but in a more general case, where the graph of java objects can grow very large, the use of eager fetch may cause unnecessary data to be loaded and the application will be slowed down. 2. Another solution is to explicitly load any lazy-loading the required fields actually hitting a method on those properties ex: contact.getEmailSet().size(). But this will result in subsequent sql firing which are required to load Groups (Child) Will also slow down the system. 3. Another solution is to include "fetch join" whi...

When you have a cycle in your domain model, beacuse sometimes you realy need it*, then with Spring JsonView, indeed you may have same problem in different cases, while converting Java objects to JSON objects, you can get en error : net.sf.json.JSONException: There is a cycle in the hierarchy! with a following unusefull stack trace:) First of all, think carefully fi you really do need this cycle in the dependency. If you don’t, remove it. If you do, the you can use, JSON filters. I will give an example code to show it. In the code, resulting JSON object will contain only id, name and description fields and values of the objects. JsonConfig config = new JsonConfig(); config.setJsonPropertyFilter(new PropertyFilter() { public boolean apply(Object source, String name, Object value) { if ("name".equals(name) || "description".equals(name) || "id".equals(name)) { return false; } ...

var panel = Ext.create('Ext.form.Panel', { id: 'businessUnit-form', url: 'createNewBusinessUnitForList.htm', ..... .... ..... }); formCmp.getForm().submit({ method:'POST', params:{ id: id, status: status, articles: aArticles }, ... ... });

someStore.getProxy().url = "xxxxx"; someStote.load(); ext 4.0.2a

Following I have given you the source code. There I am doing my update to the database by simply double click on the row and then when I am going to delete a record it will return a message as there have a data violation. up to this level the program is working in well manner. But the problem is after that delete , if I go to update any record, the proxy executes update and then destroy(delete) again. For your further ref - when I remove some records from this store without page refreshing, it seems that all previous deleted items are stored somewhere and sended to servlet on every new update. When I refresh page, first update is ok, but any next update again after removing a record accumulate previous removed records. What I do wrong and how I can fix it? ====CODE==== ============ /* Ext JS 4.0.2a */ Ext.require(['Ext.data.*', 'Ext.grid.*', 'Ext.dd.*']); Ext.define('StakeholderType', { extend: 'Ext.data.Model', field...

http://java.dzone.com/articles/extjs-spring-mvc-3-and?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+javalobby%2Ffrontpage+%28Javalobby+%2F+Java+Zone%29

extjs 4.0.2a example.. ======This should be overriden globally for use =============== Ext.data.proxy.Rest.override({ actionMethods : { create : 'POST', read : 'GET', update : 'POST', destroy: 'POST' } }); =============================================================== var jsonReader = Ext.create('Ext.data.reader.Json',{ root: 'data', totalProperty: 'total', successProperty: 'success', idProperty: 'stakeholderTypeId', messageProperty: 'message' },StakeholderType); var jsonWriter = Ext.create('Ext.data.writer.Json',{ root: 'data', encode: true, writeAllFields: true }); var proxy = Ext.create('Ext.data.proxy.Rest',{ api: { read : 'stakeholderTypeView.htm', update : 'stakeholderTypeEdit.htm', destroy : 'stakeholderTypeDelete.htm' }, r...

Then what about extjs 4.0.x??? It's a powerful framework with RESTful support. Just try it.. http://edspencer.net/

Is it creating threads from each jvm for a one request????? it's simple.... there u will be created multiple threads from each jvm but still there have only one servlet instance for the container. Are you sure this answer??? No problem if I am wrong becos u r the job finder..pls. google this now it self.

@ManyToOne(cascade=CascadeType.PERSIST) @ManyToOne(cascade=CascadeType.ALL) @ManyToOne(cascade=CascadeType.MERGE) @ManyToOne(cascade=CascadeType.REMOVE) @ManyToOne(cascade=CascadeType.REFRESH) @Transactional(propagation=Propagation.REQUIRED) @Transactional(propagation=Propagation.SUPPORTS) @RequestParam

Refer more... There have many major differences with spring rather than normal hibernate.

@Transactional And how should it be used when declaring read only and writing transactions? @Service("businessUnitListService") @Transactional(propagation=Propagation.SUPPORTS,readOnly=true) public class BusinessUnitListServiceImpl implements BusinessUnitListService { @Override @Transactional(propagation=Propagation.SUPPORTS,readOnly=true) public List getAllBusinessUnitList(Long businessUnitId) { return businessUnitListDAO.getAllBusinessUnitList(businessUnitId); } @Override @Transactional(propagation=Propagation.REQUIRED,readOnly=false) public void deleteBusinessUnitList(String data) { if (data.indexOf('[') > -1) { List deleteBusinessUnitList = businessUnitListUtil.getListIdFromJSON(data); for (Long id : deleteBusinessUnitList) { businessUnitListDAO.deleteBusinessUnitList(id); } } else { Long id = Long.parseLong(data.toString()); businessUnitListDAO.deleteBusinessUnitList(id); } } } if you missed out one of above annotation proper...

@ContextConfiguration(locations="file:src/test/resources/ApplicationContext.xml") @Transactional(propagation=Propagation.SUPPORTS,readOnly=true) public class BusinessUnitListServiceImplTest extends AbstractTransactionalJUnit38SpringContextTests{ @BeforeClass public static void setUpBeforeClass() throws Exception { } @AfterClass public static void tearDownAfterClass() throws Exception { } @Before protected void setUp() throws Exception { super.setUp(); } @After protected void tearDown() throws Exception { super.tearDown(); } public void testAddBusinessUnitList(){ //your unit testings } }

1. Transient 2. Persistence 3. Detached

cannot

with "Reflection" it can be done. http://en.wikipedia.org/wiki/Reflection_%28computer_science%29 I think I guess correctly but you are the decider which is the correct one???? hik hik.... just google it and find the answer. code for learn something public class A { private static A a = null; //singleton pattern public static A getInstance(){ if(a==null) a = new A(); return a; } void m(String msg){ System.out.println(msg); } public static void main(String[] args) { A a = getInstance(); A.B b = a.new B(); a.m("m from A"); b.x(a); } class B{ void x(A a){ A t = A.getInstance(); t.m("x from B"); System.out.println("Both of objects are the same one? "+t.equals(a)); } } }

dependency injection is the passing or setting of dependencies into a software component. DI is the most specific pattern of IOC. want to know more - follow this';; http://martinfowler.com/articles/injection.html

JSP is used mainly for presentation only. A JSP can only be HttpServlet that means the only supported protocol in JSP is HTTP. But a servlet can support any protocol like HTTP, FTP, SMTP etc. for more about jsp and servlets::: http://www.javacertificate.net/jsp_iqns.htm

just check here;;; http://www.visualbuilder.com/java/spring/tutorial/autowiring-in-spring/

This class implements the Set interface, backed by a TreeMap instance. This class guarantees that the sorted set will be in ascending element order, sorted according to the natural order of the elements (see Comparable), or by the comparator provided at set creation time, depending on which constructor is used. java.lang.Object extended by java.util.AbstractCollection extended by java.util.AbstractSet extended by java.util.TreeSet For further reference::::::: http://www.esus.com/docs/GetQuestionPage.jsp?uid=821

How can we handle errors which happening at run time when parsing an XML document through a web service? How can we detect specified error when XML was crashed or with invalid escape characters and keep record of that error to inform user? ????????? ????? ??? ?? ? I guess the answer is here... http://www.ibm.com/developerworks/library/x-saxerror/index.html

A transaction is an agreement, communication, or movement carried out between separate entities or objects, ACID properties are related to database transaction. 1)atomic 2)consistent 3)isolated 4)durable

DTO means Data Transfer Objects equivalent to POJO classess(Java beans) those are carrying data. DAO means Data Access Objects those are doing CRUD operations with DTOs or DB

public class A { public static void main(String[] args) { System.out.println(new A().m()); } public int m(){ try { throw new Exception(); } catch (Exception e) { return 0; }finally{ return 1; } } } what will be the output of this????