javax.persistence.Column Maven / Gradle / Ivy
/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the License). You may not use this file except in
* compliance with the License.
*
* You can obtain a copy of the license at
* https://glassfish.dev.java.net/public/CDDLv1.0.html or
* glassfish/bootstrap/legal/CDDLv1.0.txt.
* See the License for the specific language governing
* permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* Header Notice in each file and include the License file
* at glassfish/bootstrap/legal/CDDLv1.0.txt.
* If applicable, add the following below the CDDL Header,
* with the fields enclosed by brackets [] replaced by
* you own identifying information:
* "Portions Copyrighted [year] [name of copyright owner]"
*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
*/
package javax.persistence;
import java.lang.annotation.Target;
import java.lang.annotation.Retention;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.RetentionPolicy.RUNTIME;
/**
* Is used to specify a mapped column for a persistent property or field.
* If no Column annotation is specified, the default values are applied.
* Examples:
*
*
* Example 1:
* @Column(name="DESC", nullable=false, length=512)
* public String getDescription() { return description; }
*
* Example 2:
* @Column(name="DESC",
* columnDefinition="CLOB NOT NULL",
* table="EMP_DETAIL")
* @Lob
* public String getDescription() { return description; }
*
* Example 3:
* @Column(name="ORDER_COST", updatable=false, precision=12, scale=2)
* public BigDecimal getCost() { return cost; }
*
*
*
*
* @since Java Persistence 1.0
*/
@Target({METHOD, FIELD})
@Retention(RUNTIME)
public @interface Column {
/**
* (Optional) The name of the column. Defaults to
* the property or field name.
*/
String name() default "";
/**
* (Optional) Whether the property is a unique key. This is a
* shortcut for the UniqueConstraint annotation at the table
* level and is useful for when the unique key constraint is
* only a single field. This constraint applies in addition
* to any constraint entailed by primary key mapping and
* to constraints specified at the table level.
*/
boolean unique() default false;
/**
* (Optional) Whether the database column is nullable.
*/
boolean nullable() default true;
/**
* (Optional) Whether the column is included in SQL INSERT
* statements generated by the persistence provider.
*/
boolean insertable() default true;
/**
* (Optional) Whether the column is included in SQL UPDATE
* statements generated by the persistence provider.
*/
boolean updatable() default true;
/**
* (Optional) The SQL fragment that is used when
* generating the DDL for the column.
* Defaults to the generated SQL to create a
* column of the inferred type.
*/
String columnDefinition() default "";
/**
* (Optional) The name of the table that contains the column.
* If absent the column is assumed to be in the primary table.
*/
String table() default "";
/**
* (Optional) The column length. (Applies only if a
* string-valued column is used.)
*/
int length() default 255;
/**
* (Optional) The precision for a decimal (exact numeric)
* column. (Applies only if a decimal column is used.)
* Value must be set by developer if used when generating
* the DDL for the column.
*/
int precision() default 0;
/**
* (Optional) The scale for a decimal (exact numeric) column.
* (Applies only if a decimal column is used.)
*/
int scale() default 0;
}