eclipselink

Java/JAXB: Unmarshall Xml to specific subclass based on an attribute

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JAXB is a spec, specific implementations will provide extension points to do things such as this. If you are using EclipseLink JAXB (MOXy) you could modify the Shape class as follows: import javax.xml.bind.annotation.XmlAttribute; import org.eclipse.persistence.oxm.annotations.XmlCustomizer; @XmlCustomizer(ShapeCustomizer.class) public abstract class Shape { int points; @XmlAttribute public int getPoints() { return points; } public void setPoints(int points) … Read more

How to use Postgres JSONB datatype with JPA?

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All the answers helped me to reach the final solution that is ready for JPA and not EclipseLink or Hibernate specifically. import com.fasterxml.jackson.core.type.TypeReference; import com.fasterxml.jackson.databind.ObjectMapper; import java.io.IOException; import javax.json.Json; import javax.json.JsonObject; import javax.persistence.Converter; import org.postgresql.util.PGobject; @Converter(autoApply = true) public class JsonConverter implements javax.persistence.AttributeConverter<JsonObject, Object> { private static final long serialVersionUID = 1L; private static ObjectMapper … Read more

Manually specify the value of a primary key in JPA @GeneratedValue column

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This works with eclipselink. It will create a seperate table for the sequence, but that shouldn’t pose a problem. @Id @GeneratedValue(strategy=GenerationType.AUTO) @Column(name=”id”, insertable=true, updatable=true, unique=true, nullable=false) private Long id; GenerationType.AUTO will choose the ideal generation strategy. Since the field is specified as insertable and updateable, a TABLE generation strategy will be used. This means eclipselink … Read more

How to silently truncate strings while storing them when they are longer than the column length definition?

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One can truncate a string according to the JPA annotations in the setter for the corresponding field: public void setX(String x) { try { int size = getClass().getDeclaredField(“x”).getAnnotation(Column.class).length(); int inLength = x.length(); if (inLength>size) { x = x.substring(0, size); } } catch (NoSuchFieldException ex) { } catch (SecurityException ex) { } this.x = x; } … Read more