How about

    Query q = 
      em.createQuery(
        &quot;SELECT x FROM org.SomeTable x WHERE x.someString LIKE :someSymbol&quot;
    );
    q.setParameter(&quot;someSymbol&quot;, &quot;%someSubstring%&quot;);

I&#39;m pretty sure I once solved your problem like that.

For reference, you could also use CONCAT:

    like CONCAT(&#39;%&#39;, :someSymbol, &#39;%&#39;)

 query.setParameter(someSymbol, &quot;%&quot; + someSymbol+ &quot;%&quot;); 

I need to store a JSONArray object as a string then retrieve the string and convert it back to a JSONArray.  

If I do:

    JSONArray jArray;
    String s = jArray.toString()
    JSONArray newJArray = new JSONArray(s);

Will I get back the same object? 

I&#39;m trying to store a JSONArray in a SQLite database.

Here&#39;s what I&#39;m looking at. [http://developer.android.com/reference/org/json/JSONArray.html#toString()][1]


  [1]: http://developer.android.com/reference/org/json/JSONArray.html#toString%28%29

Converting from JSONArray to String then back again

I don&#39;t use Stored procedures very often and was wondering if it made sense to wrap my select queries in a transaction.

My procedure has three simple select queries, two of which use the returned value of the first.

Use transactions for select statements?

How would I specify a JPA query like:

    Query q = 
      em.createQuery(
        &quot;SELECT x FROM org.SomeTable x WHERE x.someString LIKE &#39;%:someSymbol%&#39;&quot;
      );

followed by:

    q.setParameter(&quot;someSymbol&quot;, &quot;someSubstring&quot;);

and not triggering a

    org.hibernate.QueryParameterException: could not locate named parameter [id]

Much appreciated!

How to specify a JPA named parameter surrounded by wildcards?

How would I specify a JPA query like:
<pre><code class="hljs language-css">Query q = 
 em.createQuery(
 "SELECT x FROM org.SomeTable x WHERE x.someString LIKE '%:someSymbol%'"
 );
</code></pre>
followed by:
<pre><code class="hljs language-less">q.setParameter("someSymbol", "someSubstring");
</code></pre>
and not triggering a
<pre><code class="hljs language-bash">org.hibernate.QueryParameterException: could not locate named parameter [id]
</code></pre>
Much appreciated!

    &lt;%@ taglib prefix=&quot;c&quot; uri=&quot;http://java.sun.com/jsp/jstl/core&quot; %&gt;
    &lt;%@ page import=&quot;com.library.controller.*&quot;%&gt;
    &lt;%@ page import=&quot;com.library.dao.*&quot; %&gt;
    &lt;%@ page import=&quot;java.util.*&quot; %&gt;
    &lt;%@ page import=&quot;java.lang.*&quot; %&gt;
    &lt;%@ page import=&quot;java.util.Date&quot; %&gt;
    &lt;meta http-equiv=&quot;Content-Type&quot; content=&quot;text/html; charset=ISO-8859-1&quot;&gt;
    &lt;title&gt;Return Page&lt;/title&gt;
    &lt;/head&gt;
    &lt;body bgcolor=&quot;#aabcde&quot;&gt;
    &lt;div align=&quot;right&quot;&gt;&lt;a href=&quot;Login.jsp&quot;&gt;Logout&lt;/a&gt;&lt;/div&gt;
    &lt;table align=&quot;center&quot; border=&quot;2&quot; cellspacing=&quot;3&quot; cellpadding=&quot;3&quot;&gt;
    &lt;tr&gt;&lt;th&gt;BookID&lt;/th&gt;&lt;th&gt;BookName&lt;/th&gt;&lt;th&gt;Issuedate&lt;/th&gt;&lt;th&gt;returndate&lt;/th&gt;&lt;/tr&gt;
    &lt;c:forEach var=&quot;element&quot; items=&quot;${list}&quot;&gt;
        &lt;tr&gt;
            &lt;td&gt;${element.getBookid}&lt;/td&gt;&lt;td&gt;${element.getBookname()}&lt;/td&gt;  
            &lt;td&gt;${element.getIssuedate()}&lt;/td&gt;&lt;td&gt;${element.getReturndate()}&lt;/td&gt;
        &lt;/tr&gt;
    &lt;/c:forEach&gt;
The Eclipse IDE is showing red underline and when I focus it the tag is : can not find the library descriptor for http://java.sun.com/jsp/jstl/core

How to resolve : Can not find the tag library descriptor for &quot;http://java.sun.com/jsp/jstl/core&quot;

I need web access from Gradle through a proxy server to use the Gradle/Artifactory integration for Jenkins. To reduce possible causes for issues, I manually add the Artifactory plugin in build.gradle and run it from command line:

    apply {
        apply from: &quot;http://gradle.artifactoryonline.com/gradle/plugins/org/jfrog/buildinfo/build-info-extractor-gradle/1.0.1/artifactoryplugin-1.0.1.gradle&quot;
    }

Following [this](http://gradle.org/releases/0.8/docs/userguide/tutorial_this_and_that.html#sec:accessing_the_web_via_a_proxy) description I specified the following in .gradle/gradle.properties in my home directory:

    systemProp.http.proxyHost=hostname
    systemProp.http.proxyPort=8080
    systemProp.http.proxyUser=de\\username
    systemProp.http.proxyPassword=xxx

With the above proxy configuration (that is otherwise known to work), it fails:

&gt; 11:33:17.699 [ERROR] [org.gradle.BuildExceptionReporter] Caused by: java.io.IOException: Server returned HTTP response code: 407 for URL: http://gradle.artifactoryonline.com/gradle/plugins/org/jfrog/buildinfo/build-info-extractor-gradle/1.0.1/artifactoryplugin-1.0.1.gradle

I have two proxy servers to choose from, and one always responds with `407` (*Proxy authentication required*), the other with `502` (*Bad gateway*), so obviously, the proxyHost and proxyPort options are used.

As the user name (based on an Active Directory user) contains a backslash, I tried both `\\` and `\`, but neither worked. The user specified is different from the user that is logged in to the machine and Active Directory. This user&#39;s credentials aren&#39;t valid for the proxy, so I need to be able to specify a different user.

Setting the same options in Jenkins&#39; or Artifactory&#39;s GUI worked.


Gradle proxy configuration

Are there any OpenJDK installers available for Windows, possibly with free updates for a longer time than Oracle offers? The OpenJDK home page (http://openjdk.java.net/) offers only ZIP files.

OpenJDK availability for Windows OS

I need to split a string base on delimiter `-` and `.`. Below are my desired output. 

`AA.BB-CC-DD.zip` -&gt; 

    AA
    BB
    CC
    DD
    zip 

but my following code does not work.

    private void getId(String pdfName){
        String[]tokens = pdfName.split(&quot;-\\.&quot;);
    }

Use String.split() with multiple delimiters

I&#39;ve been working with JPA (implementation Hibernate) for some time now and each time I need to create entities I find myself struggling with issues as AccessType, immutable properties, equals/hashCode, ... .  
So I decided to try and find out the general best practice for each issue and write this down for personal use.  
I would not mind however for anyone to comment on it or to tell me where I&#39;m wrong.

Entity Class
---- 

* implement Serializable  

  Reason: _The specification says you have to, but some JPA providers do not enforce this. Hibernate as JPA provider does not enforce this, but it can fail somewhere deep in its stomach with ClassCastException, if Serializable has not been implemented._

Constructors
------------
* create a constructor with all required fields of the entity 

  _Reason: A constructor should always leave the instance created in a sane state._  
* besides this constructor: have a package private default constructor  

  _Reason: Default constructor is required to have Hibernate initialize the entity; private is allowed but package private (or public) visibility is required for runtime proxy generation and efficient data retrieval without bytecode instrumentation._

  
Fields/Properties
------

* Use field access in general and property access when needed  

  *Reason:  this is probably the most debatable issue since there are no clear and convincing  arguments for one or the other (property access vs field access); however, field access seems to be general favourite because of clearer code, better encapsulation and no need to create setters for immutable fields* 

* Omit setters for immutable fields (not required for access type field)
* properties may be private  
  Reason: I once heard that protected is better for (Hibernate) performance but all I can find on the web is: *Hibernate can access public, private, and protected accessor methods, as well as public, private and protected fields directly. The choice is up to you and you can match it to fit your application design.*


Equals/hashCode
----

* Never use a generated id if this id is only set when persisting the entity
* By preference: use immutable values to form a unique Business Key and use this to test equality
* if a unique Business Key is not available use a non-transient **UUID** which is created when the entity is initialised; See [this great article][1] for more information.
* **never** refer to related entities (ManyToOne); if this entity (like a parent entity) needs to be part of the Business Key then compare the ID&#39;s only. Calling getId() on a proxy will not trigger the loading of the entity, as long as you&#39;re using [property access type][2].


Example Entity
----


    @Entity
    @Table(name = &quot;ROOM&quot;)
    public class Room implements Serializable {
    
        private static final long serialVersionUID = 1L;
    
        @Id
        @GeneratedValue
        @Column(name = &quot;room_id&quot;)
        private Integer id;
    
        @Column(name = &quot;number&quot;) 
        private String number; //immutable
    
        @Column(name = &quot;capacity&quot;)
        private Integer capacity;
    
        @ManyToOne(fetch = FetchType.LAZY, optional = false)
        @JoinColumn(name = &quot;building_id&quot;)
        private Building building; //immutable
    
        Room() {
            // default constructor
        }
    
        public Room(Building building, String number) {
            // constructor with required field
            notNull(building, &quot;Method called with null parameter (application)&quot;);
            notNull(number, &quot;Method called with null parameter (name)&quot;);
    
            this.building = building;
            this.number = number;
        }
    
        @Override
        public boolean equals(final Object otherObj) {
            if ((otherObj == null) || !(otherObj instanceof Room)) {
                return false;
            }
            // a room can be uniquely identified by it&#39;s number and the building it belongs to; normally I would use a UUID in any case but this is just to illustrate the usage of getId()
            final Room other = (Room) otherObj;
            return new EqualsBuilder().append(getNumber(), other.getNumber())
                    .append(getBuilding().getId(), other.getBuilding().getId())
                    .isEquals();
            //this assumes that Building.id is annotated with @Access(value = AccessType.PROPERTY) 
        }
    
        public Building getBuilding() {
            return building;
        }
    
    
        public Integer getId() {
            return id;
        }
    
        public String getNumber() {
            return number;
        }
    
        @Override
        public int hashCode() {
            return new HashCodeBuilder().append(getNumber()).append(getBuilding().getId()).toHashCode();
        }
    
        public void setCapacity(Integer capacity) {
            this.capacity = capacity;
        }

        //no setters for number, building nor id
    
    }

Other suggestions to add to this list are more than welcome...

**UPDATE**

Since reading [this article][1] I have adapted my way of implementing eq/hC:

 - if an immutable simple business key is available: use that
 - in all other cases: use a uuid

  [1]: https://web.archive.org/web/20171211235806/http://www.onjava.com/pub/a/onjava/2006/09/13/dont-let-hibernate-steal-your-identity.html
  [2]: https://stackoverflow.com/questions/3736818/hibernate-generating-sql-queries-when-accessing-associated-entitys-id/3739197#3739197

Create the perfect JPA entity

What is difference between `setMaxResults` and `setFetchSize` in org.hibernate.Query? I just can no get it =)

What is difference between setMaxResults and setFetchSize in org.hibernate.Query?

Although this question asked many times and I have already used all the suggestion but still I am getting this error.

The User.java is

    @Entity
	@Table(name = &quot;USER&quot;)
	public class User implements UserDetails, Serializable {
	
		private static final long serialVersionUID = 2L;
	
		@Id
		@Column(name = &quot;USER_ID&quot;)
		@GeneratedValue(strategy = GenerationType.IDENTITY)
		private long id;
		@Column(name = &quot;USERNAME&quot;)
		private String username;
		@Column(name = &quot;PASSWORD&quot;)
		private String password;
		@Column(name = &quot;NAME&quot;)
		private String name;
		@Column(name = &quot;EMAIL&quot;)
		private String email;
		@Column(name = &quot;LOCKED&quot;)
		private boolean locked;
		@OneToMany(cascade=CascadeType.ALL, fetch = FetchType.EAGER)
		@ElementCollection(targetClass=Role.class)
		@Column(name = &quot;ROLE_ID&quot;)
		private Set&lt;Role&gt; roles;
	
		@Override
		public GrantedAuthority[] getAuthorities() {
			List&lt;GrantedAuthorityImpl&gt; list = new ArrayList&lt;GrantedAuthorityImpl&gt;(0);
			for (Role role : roles) {
				list.add(new GrantedAuthorityImpl(role.getRole()));
			}
			return (GrantedAuthority[]) list.toArray(new GrantedAuthority[list.size()]);
		}
	
		@Override
		public boolean isAccountNonExpired() {
			return true;
		}
	
		@Override
		public boolean isAccountNonLocked() {
			return !isLocked();
		}
	
		@Override
		public boolean isCredentialsNonExpired() {
			return true;
		}
	
		@Override
		public boolean isEnabled() {
			return true;
		}
	
		public long getId() {
			return id;
		}
	
		public void setId(long id) {
			this.id = id;
		}
	
		public String getName() {
			return name;
		}
	
		public void setName(String name) {
			this.name = name;
		}
	
		public String getEmail() {
			return email;
		}
	
		public void setEmail(String email) {
			this.email = email;
		}
	
		public boolean isLocked() {
			return locked;
		}
	
		public void setLocked(boolean locked) {
			this.locked = locked;
		}
	
		@Override
		public String getUsername() {
			return username;
		}
	
		public void setUsername(String username) {
			this.username = username;
		}
	
		@Override
		public String getPassword() {
			return password;
		}
	
		public void setPassword(String password) {
			this.password = password;
		}
	
		public void setRoles(Set&lt;Role&gt; roles) {
			this.roles = roles;
		}
	
		public Set&lt;Role&gt; getRoles() {
			return roles;
		}
	}

And the Role.java is

    @Entity
	@Table(name=&quot;ROLE&quot;)
	public class Role implements Serializable {
	
		@Id
		@GeneratedValue(strategy = GenerationType.IDENTITY)
		@Column(name=&quot;ROLE_ID&quot;)
		private long id;
		@Column(name=&quot;USERNAME&quot;)
		private String username;
		@Column(name=&quot;ROLE&quot;)
		private String role;
	
		
		public long getId() {
			return id;
		}
	
		public void setId(long id) {
			this.id = id;
		}
	
		public String getUsername() {
			return username;
		}
	
		public void setUsername(String username) {
			this.username = username;
		}
	
		public String getRole() {
			return role;
		}
	
		public void setRole(String role) {
			this.role = role;
		}
	}

This is my first attempt in hibernate annotation with JPA. So any suggestions will be very helpful. 

For hibernate the pom.xml&#39;s dependencies are:

        &lt;dependency&gt;
			&lt;groupId&gt;org.hibernate&lt;/groupId&gt;
			&lt;artifactId&gt;hibernate&lt;/artifactId&gt;
			&lt;version&gt;3.5.4-Final&lt;/version&gt;
			&lt;type&gt;pom&lt;/type&gt;
			&lt;scope&gt;compile&lt;/scope&gt;
		&lt;/dependency&gt;
		&lt;dependency&gt;
			&lt;groupId&gt;org.hibernate&lt;/groupId&gt;
			&lt;artifactId&gt;hibernate-annotations&lt;/artifactId&gt;
			&lt;version&gt;3.5.4-Final&lt;/version&gt;
			&lt;type&gt;jar&lt;/type&gt;
			&lt;scope&gt;compile&lt;/scope&gt;
		&lt;/dependency&gt;
		
		&lt;dependency&gt;
			&lt;groupId&gt;org.hibernate&lt;/groupId&gt;
			&lt;artifactId&gt;hibernate-core&lt;/artifactId&gt;
			&lt;version&gt;3.5.4-Final&lt;/version&gt;
			&lt;type&gt;jar&lt;/type&gt;
			&lt;scope&gt;compile&lt;/scope&gt;
		&lt;/dependency&gt;
		&lt;dependency&gt;
			&lt;groupId&gt;org.hibernate&lt;/groupId&gt;
			&lt;artifactId&gt;hibernate-validator&lt;/artifactId&gt;
			&lt;version&gt;3.1.0.GA&lt;/version&gt;
			&lt;type&gt;jar&lt;/type&gt;
			&lt;scope&gt;compile&lt;/scope&gt;
		&lt;/dependency&gt;
		&lt;dependency&gt;
			&lt;groupId&gt;org.hibernate&lt;/groupId&gt;
			&lt;artifactId&gt;hibernate-entitymanager&lt;/artifactId&gt;
			&lt;version&gt;3.5.4-Final&lt;/version&gt;
			&lt;type&gt;jar&lt;/type&gt;
			&lt;scope&gt;compile&lt;/scope&gt;
		&lt;/dependency&gt;

I have no clue about the fault.

Thanks.

org.hibernate.MappingException: Could not determine type for: java.util.Set

I&#39;m using my uuid as following:

    @Id
	@GeneratedValue(generator = &quot;uuid&quot;)
	@GenericGenerator(name = &quot;uuid&quot;, strategy = &quot;uuid&quot;)
	@Column(name = &quot;uuid&quot;, unique = true)
	private String uuid;

but I&#39;m getting a smart Hibernate warning:

&gt; Using
&gt; org.hibernate.id.UUIDHexGenerator
&gt; which does not generate IETF RFC 4122
&gt; compliant UUID values; consider using
&gt; org.hibernate.id.UUIDGenerator instead

So I want to switch to `org.hibernate.id.UUIDGenerator`, now my question is how should I tell it to Hibernate&#39;s generator. I saw some guy used it as a &quot;hibernate-uuid&quot; - so this is what I&#39;ve tried, but with negative result:

    @Id
	@GeneratedValue(generator = &quot;hibernate-uuid&quot;)
	@GenericGenerator(name = &quot;hibernate-uuid&quot;, strategy = &quot;hibernate-uuid&quot;)
	@Column(name = &quot;uuid&quot;, unique = true)
	private String uuid;




Using Hibernate UUIDGenerator via annotations

I had successfully written my first master child example with hibernate. After few days I took it again and upgraded some libraries. No sure what did I do but I could never make it run again. Would somebody help my figure out what is wrong in code that is returning following error message:

    org.hibernate.PersistentObjectException: detached entity passed to persist: example.forms.InvoiceItem
    	at org.hibernate.event.def.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:127)
    	at org.hibernate.impl.SessionImpl.firePersist(SessionImpl.java:799)
    	at org.hibernate.impl.SessionImpl.persist(SessionImpl.java:791)
    	.... (truncated)

hibernate mapping:

    &lt;hibernate-mapping package=&quot;example.forms&quot;&gt;
    	&lt;class name=&quot;Invoice&quot; table=&quot;Invoices&quot;&gt;
    		&lt;id name=&quot;id&quot; type=&quot;long&quot;&gt;
    			&lt;generator class=&quot;native&quot; /&gt;
    		&lt;/id&gt;
    		&lt;property name=&quot;invDate&quot; type=&quot;timestamp&quot; /&gt;
    		&lt;property name=&quot;customerId&quot; type=&quot;int&quot; /&gt;
    		&lt;set cascade=&quot;all&quot; inverse=&quot;true&quot; lazy=&quot;true&quot; name=&quot;items&quot; order-by=&quot;id&quot;&gt;
    			&lt;key column=&quot;invoiceId&quot; /&gt;
    			&lt;one-to-many class=&quot;InvoiceItem&quot; /&gt;
    		&lt;/set&gt;
    	&lt;/class&gt;
    	&lt;class name=&quot;InvoiceItem&quot; table=&quot;InvoiceItems&quot;&gt;
    		&lt;id column=&quot;id&quot; name=&quot;itemId&quot; type=&quot;long&quot;&gt;
    			&lt;generator class=&quot;native&quot; /&gt;
    		&lt;/id&gt;
    		&lt;property name=&quot;productId&quot; type=&quot;long&quot; /&gt;
    		&lt;property name=&quot;packname&quot; type=&quot;string&quot; /&gt;
    		&lt;property name=&quot;quantity&quot; type=&quot;int&quot; /&gt;
    		&lt;property name=&quot;price&quot; type=&quot;double&quot; /&gt;
    		&lt;many-to-one class=&quot;example.forms.Invoice&quot; column=&quot;invoiceId&quot; name=&quot;invoice&quot; not-null=&quot;true&quot; /&gt;
    	&lt;/class&gt;
    &lt;/hibernate-mapping&gt;
**EDIT:** InvoiceManager.java

    class InvoiceManager {
    
    	public Long save(Invoice theInvoice) throws RemoteException {
    		Session session = HbmUtils.getSessionFactory().getCurrentSession();
    		Transaction tx = null;
    		Long id = null;
    		try {
    			tx = session.beginTransaction();
    			session.persist(theInvoice);
    			tx.commit();
    			id = theInvoice.getId();
    		} catch (RuntimeException e) {
    			if (tx != null)
    				tx.rollback();
    			e.printStackTrace();
    			throw new RemoteException(&quot;Invoice could not be saved&quot;);
    		} finally {
    			if (session.isOpen())
    				session.close();
    		}
    		return id;
    	}
    
    	public Invoice getInvoice(Long cid) throws RemoteException {
    		Session session = HbmUtils.getSessionFactory().getCurrentSession();
    		Transaction tx = null;
    		Invoice theInvoice = null;
    		try {
    			tx = session.beginTransaction();
    			Query q = session
    					.createQuery(
    							&quot;from Invoice as invoice &quot; +
    							&quot;left join fetch invoice.items as invoiceItems &quot; +
    							&quot;where invoice.id = :id &quot;)
    					.setReadOnly(true);
    			q.setParameter(&quot;id&quot;, cid);
    			theInvoice = (Invoice) q.uniqueResult();
    			tx.commit();
    		} catch (RuntimeException e) {
    			tx.rollback();
    		} finally {
    			if (session.isOpen())
    				session.close();
    		}
    		return theInvoice;
    	}
    }

Invoice.java

    public class Invoice implements java.io.Serializable {
    
    	private Long id;
    	private Date invDate;
    	private int customerId;
    	private Set&lt;InvoiceItem&gt; items;
    
    	public Long getId() {
    		return id;
    	}
    
    	public Date getInvDate() {
    		return invDate;
    	}
    
    	public int getCustomerId() {
    		return customerId;
    	}
    
    	public Set&lt;InvoiceItem&gt; getItems() {
    		return items;
    	}
    
    	void setId(Long id) {
    		this.id = id;
    	}
    
    	void setInvDate(Date invDate) {
    		this.invDate = invDate;
    	}
    
    	void setCustomerId(int customerId) {
    		this.customerId = customerId;
    	}
    
    	void setItems(Set&lt;InvoiceItem&gt; items) {
    		this.items = items;
    	}
    }

InvoiceItem.java

    public class InvoiceItem implements java.io.Serializable {
    
    	private Long itemId;
    	private long productId;
    	private String packname;
    	private int quantity;
    	private double price;
    	private Invoice invoice;
    
    	public Long getItemId() {
    		return itemId;
    	}
    
    	public long getProductId() {
    		return productId;
    	}
    
    	public String getPackname() {
    		return packname;
    	}
    
    	public int getQuantity() {
    		return quantity;
    	}
    
    	public double getPrice() {
    		return price;
    	}
    
    	public Invoice getInvoice() {
    		return invoice;
    	}
    
    	void setItemId(Long itemId) {
    		this.itemId = itemId;
    	}
    
    	void setProductId(long productId) {
    		this.productId = productId;
    	}
    
    	void setPackname(String packname) {
    		this.packname = packname;
    	}
    
    	void setQuantity(int quantity) {
    		this.quantity = quantity;
    	}
    
    	void setPrice(double price) {
    		this.price = price;
    	}
    
    	void setInvoice(Invoice invoice) {
    		this.invoice = invoice;
    	}
    }
**EDIT:** JSON object sent from client:

    {&quot;id&quot;:null,&quot;customerId&quot;:3,&quot;invDate&quot;:&quot;2005-06-07T04:00:00.000Z&quot;,&quot;items&quot;:[
    {&quot;itemId&quot;:1,&quot;productId&quot;:1,&quot;quantity&quot;:10,&quot;price&quot;:100},
    {&quot;itemId&quot;:2,&quot;productId&quot;:2,&quot;quantity&quot;:20,&quot;price&quot;:200},
    {&quot;itemId&quot;:3,&quot;productId&quot;:3,&quot;quantity&quot;:30,&quot;price&quot;:300}]}

**EDIT:** Some details:  
I have tried to save invoice by following two ways:

 1. Manually fabricated above mentioned
    json object and passed it to fresh
    session of server. In this case absolutely 
    no activity has been made prior to calling 
    save method so there should not be any open session
    except the one opened in save method

 2. Loaded existing data by using
    getInvoice method and them passed same 
    data after removing key value. This too I believe
    should close the session before saving as
    transaction is being committed in getInvoice method.

In both cases I am getting same error message that is forcing me to believe that something is wrong either with hibernate configuration file or entity classes or save method.  
  
**Please let me know if I should provide more details**

org.hibernate.PersistentObjectException: detached entity passed to persist

I know I can pass a list to named query in JPA, but how about NamedNativeQuery? I have tried many ways but still can&#39;t just pass the list to a NamedNativeQuery. Anyone know how to pass a list to the in clause in NamedNativeQuery? Thank you very much!

The NamedNativeQuery is as below:

    @NamedNativeQuery(
       name=&quot;User.findByUserIdList&quot;, 
       query=&quot;select u.user_id, u.dob, u.name, u.sex, u.address from user u &quot;+
             &quot;where u.user_id in (?userIdList)&quot;
    )

and it is called like this:

    List&lt;Object[]&gt; userList = em.createNamedQuery(&quot;User.findByUserIdList&quot;).setParameter(&quot;userIdList&quot;, list).getResultList();

However the result is not as I expected.

    System.out.println(userList.size());  //output 1

    Object[] user = userList.get(0);
    System.out.println(user.length);   //expected 5 but result is 3
    System.out.println(user[0]);       //output MDAVERSION which is not a user_id
    System.out.println(user[1]);       //output 5
    System.out.println(user[2]);       //output 7


JPA passing list to IN clause in named native query

Is there any difference if I use

    @OneToMany
	public Set&lt;Rating&gt; ratings;

or if I use

    @OneToMany
	public List&lt;Rating&gt; ratings;

both work OK, i know difference between list and a set, however I don&#39;t know if this makes any difference how hibernate (or rather JPA 2.0) handles it.

@OneToMany List&lt;&gt; vs Set&lt;&gt; difference

It&#39;s possible to define enumerations in JPA using either

    @Enumerated(EnumType.ORDINAL)
or

    @Enumerated(EnumType.STRING)

I wonder what are advantages and disadvantages of those two definitions? 

I heard that ORDINAL performs better (is faster) than STRING with EclipseLink.  
Is that true?
  

JPA Enum ORDINAL vs STRING

I find the named parameters feature in C# quite useful in some cases.

    calculateBMI(70, height: 175);

What can I use if I want this in JavaScript? 

---

What I don’t want is this:

    myFunction({ param1: 70, param2: 175 });

    function myFunction(params){
      // Check if params is an object
      // Check if the parameters I need are non-null
      // Blah blah
    }

That approach I’ve already used. Is there another way?

I’m okay using any library to do this.

Is there a way to provide named parameters in a function call in JavaScript?

Dart supports both named optional parameters and positional optional parameters. What are the differences between the two?

Also, how can you tell if an optional parameter was actually specified?

What is the difference between named and positional parameters in Dart?

I have method

    def test(String a, String b) { }

and I would like to call this with a dynamic parameter map.
I always though that

    test([&#39;1&#39;,&#39;2&#39;]); //valid call

and also 
 
    test([a:&#39;1&#39;,b:&#39;2&#39;]); //=&gt; does not work

will work. but it doesn&#39;t. So I remembered [the spread operator][1], but can&#39;t get it to work....

Is there a way to call a method like the one above with some kind of map as parameter instead of single parameters?


  [1]: https://groovy-lang.org/operators.html#_spread_operator

Named parameters

I have this Function in a class:

    func multiply(factor1:Int, factor2:Int) -&gt; Int{
        return factor1 * factor2
    }

I try to call the function using this:

    var multResult = calculator.multiply(9834, 2321)

The problem is that the compiler wants it to look more like this:

    var multResult = calculator.multiply(9834, factor2: 2321)

Why does the first one cause an error? 

Content Type	Original Author	Original Content on Stackoverflow
Question	Reuben Peter-Paul	View Question on Stackoverflow
Solution 1 - Java	musiKk	View Answer on Stackoverflow
Solution 2 - Java	xtian	View Answer on Stackoverflow
Solution 3 - Java	Chinmoy	View Answer on Stackoverflow

How to specify a JPA named parameter surrounded by wildcards?

Java Problem Overview

Java Solutions

Solution 1 - Java

Solution 2 - Java

Solution 3 - Java

Use transactions for select statements?

Converting from JSONArray to String then back again

Attributions