JPA utf-8 characters not persisted - jpa

Question

I have a simple web application where I use JPA.
I have an entity called BlogEntry.
When I submit a new BlogEntry, when I debug my application I see the utf8 characters just fine.
For example
em.persist(entity);
In this line, if I debug for example:
entity.getTitle()
I can successfuly see utf-8 characters in the IDE. ( like ğğ, or çç )
Also, my database has UTF8 collation and I can insert utf-8 characters just fine with sql using like "INSERT INTO..."
However, with JPA, the characters are persisted as ????
Why might this be?
Regards.
Here is my persistence.xml:
<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence" version="2.0">
<persistence-unit name="Persistence">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<class>com.tugay.blog.core.model.Blogentry</class>
<properties>
<property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver"/>
<property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/blogdatabase"/>
<property name="javax.persistence.jdbc.user" value="root"/>
<property name="javax.persistence.jdbc.password" value="aabbccdd"/>
</properties>
</persistence-unit>
</persistence>

Answer 1

use the character encoding in the property of persistence.xml file
<property name="javax.persistence.jdbc.url"
value="jdbc:mysql://localhost:3306/blogdatabase?useUnicode=yes&characterEncoding=UTF-8"/>

Answer 2

This helped in Spring Boot:
spring.datasource.url=jdbc:mysql://localhost:3306/securitydb?useUnicode=yes&characterEncoding=UTF-8

Answer 3

This solved it nicely:
<property name="hibernate.connection.useUnicode" value="true" />
<property name="hibernate.connection.characterEncoding" value="UTF-8" />
Edit: with hibernate 4.3.1 this works:
<property name="connection.useUnicode">true</property>
<property name="connection.characterEncoding">utf-8</property>

Answer 4

Another common mistake can be the wrong encoding of the database.
If you just cerated the database without the correct encoding this error can also be a result.
use
create database mydb character set utf8 collate utf8_general_ci;
instead of
create database mydb;