Hibernate Tools Reference Guide
Hibernate Tools Reference Guide
Hibernate Tools is a toolset for Hibernate 3 and related projects. The tools provide Ant tasks and Eclipse plugins for performing reverse engineering, code generation, visualization and interaction with Hibernate.
Chapter 1. Download and install Hibernate Tools
Hibernate tools can be used "standalone" via Ant 1.6.x or fully integrated into a Eclipse 3.1.x based IDE, such as JBoss Eclipse IDE or a default Eclipse 3.1.x installation. The following describes the install steps in these environments.
1.1. JBoss Eclipse IDE
JBoss Eclipse IDE 1.5.x includes Hibernate Tools and thus nothing is required besides downloading and installing JBoss Eclipse IDE. If you need to update to a newer version of the Hibernate Tools just follow the instructions in the Eclipse IDE section.
1.2. Eclipse IDE
To install into any Eclipse 3.1.x based Eclipse IDE you can either download the Hibernate Tools distribution from the Hibernate website or use the Eclipse updatesite (see http://tools.hibernate.org for download links).
If you download the Hibernate Tools distribution you need to place the /plugins and /feature directory into your eclipse directory or eclipse extensions directory. Sometimes Eclipse does not automatically detect new plugins and thus the tools will not be activated. To ensure eclipse sees these changes run eclipse with the -clean option. E.g. eclipse -clean Using the updatesite does not require any additional steps.
Tip: If you need more basic instructions on installing plugins and general usage of eclipse then check out https://eclipse-tutorial.dev.java.net/ and especially https://eclipse-tutorial.dev.java.net/visual-tutorials/updatemanager.html which covers using the update manager.
1.2.1. Usage of Eclipse WTP
The Hibernate tools plugins currently uses WTP 1.0 which at this time is the latest stable release from the Eclipse Webtools project.
Because the WTP project have not proper versioned their plugins there might exist WTP plugins in your existing eclipse directory from other Eclipse based projects that are from an earlier WTP release but has either the same version number or higher. It is thus recommended that if you have issues with WTP provided features to try and install the plugins on a clean install of eclipse to ensure there are no version-collisions.
The tools only include a subset of the WTP 1.0 plugins, thus if you want full access to the WTP functionallity the full WTP 1.0 SDK can be installed on top of the plugins without any problems.
1.3. Ant
To use the tools via Ant you need the hibernate-tools.jar and associated libraries. The libraries are included in the distribution from the Hibernate website and the Eclipse updatesite. The libraries are located in the eclipse plugins directory at /plugins/org.hibernate.eclipse.x.x.x/lib/tools/. These libraries are 100% independent from the eclipse platform. How to use these via ant tasks are described in the Ant chapter.
Chapter 2. Code generation architecture
The code generation mechanism in the Hibernate Tools consists of a few core concepts. This section explains their overall structure which are the same for the Ant and Eclipse tools.
2.1. Hibernate Meta Model
The meta model is the model used by Hibernate core to perform its object relational mapping. The model includes information about tables, columns, classes, properties, components, values, collections etc. The API is in org.hibernate.mapping and its main entry point is the Configuration class, the same class that is used to build a session factory.
The model represented by the Configuration class can be build in many ways. The best known is by using hbm.xml files to describe the meta model, other methods are using annotations in java source code and a third is reading JDBC metadata and build a configuration. The last method is provided via the reverse engineering part of the hibernate tools.
The code generation is done based on this model no matter which method have been used to create the meta model, and thus the code generation is independent on the source of the meta model and represented via Exporters.
2.2. Exporters
Code generation is done in so called Exporters. An Exporter is handed a Hibernate Meta Model represented as a Configuration instance and it is then the job of the exporter to generate a set of code artifacts.
The tools provides a default set of Exporter's which can be used in both Ant and the Eclipse UI. Documentation for these Exporters is in the Ant and Eclipse sections.
Users can provide their own customer Exporter's, either by custom classes implementing the Exporter interface or simply be providing custom templates. This is documented at Section 4.1.3.6, “Generic Hibernate metamodel exporter (
NOTICE: This release uses Velocity for the templates. The next release might move to an alternative template engine.
Chapter 3. Eclipse Plugins
3.1. Introduction
The following features are available in the Hibernate Tools Eclipse plugins:
Mapping Editor: An editor for Hibernate XML mapping files, supporting auto-completion and syntax highlighting. It also supports semantic auto-completion for class names and property/field names, making it much more versatile than a normal XML editor.
Hibernate Console: The console is a new perspetive in Eclipse. It provides an overview of your Hibernate Console configurations, were also get an interactive view of your persistent classes and their relationships. The console allows you to execute HQL queries against your database and browse the result directly in Eclipse.
Configuration Wizards and Code generation: A set of wizards are provided with the Hibernate Eclipse tools; you can use a wizard to quickly generate common Hibernate configuration (cfg.xml) files, and from these you can code generate a series of various artifacts, there is even support for completely reverse engineer an existing database schema and use the code generation to generate POJO source files and Hibernate mapping files.
Please note that these tools do not try to hide any functionality of Hibernate. The tools make working with Hibernate easier, but you are still encouraged/required to read the documentation for Hibernate to fully utilize Hibernate Tools and especially Hibernate it self.
3.2. Creating a Hibernate configuration file
To be able to reverse engineer, prototype queries, and of course to simply use Hibernate a hibernate.properties or hibernate.cfg.xml file is needed. The Hibernate Tools provide a wizard for generating the hibernate.cfg.xml file if you do not already have such file.
Start the wizard by clicking "New Wizard" (Ctrl+N), select the Hibernate/Hibernate Configuration file (cfg.xml) wizard and press "Next". After selecting the wanted location for the hibernate.cfg.xml file, you will see the following page:
Tip: The contents in the combo boxes for the JDBC driver class and JDBC URL change automatically, depending on the Dialect and actual driver you have chosen.
Enter your configuration information in this dialog. Details about the configuration options can be found in Hibernate reference documentation.
Press "Finish" to create the configuration file, after optionally creating a Console onfiguration, the hibernate.cfg.xml will be automatically opened in an editor. The last option "Create Console Configuration" is enabled by default and when enabled i will automatically use the hibernate.cfg.xml for the basis of a "Console Configuration"
3.3. Creating a Hibernate Console configuration
You create a console configuration by running the Console Configuration wizard, shown in the following screenshot. The same wizard will also be used if you are coming from the hibernate.cfg.xml wizard and had enabled "Create Console Configuration".
The following table describes the available settings. The wizard can automatically detect default values for most of these if you started the Wizard with the relevant java project selected
Table 3.1. Hibernate Console Configuration Parameters
| Parameter |
Description |
Auto detected value |
|---|---|---|
| Name |
The unique name of the configuration |
Name of the selected project |
| Property file |
Path to a hibernate.properties file |
First hibernate.properties file found in the selected project |
| Configuration file |
Path to a hibernate.cfg.xml file |
First hibernate.cfg.xml file found in the selected project |
| Entity resolver |
Fully qualified classname of a custom EntityResolver. Only required if you have special xml entity includes in your mapping files. |
No default value |
| Enable Hibernate ejb3/annotations |
Selecting this option enables usage of annotated classes. hbm.xml files are of course still possible to use too. This feature requires running the Eclipse IDE with a JDK 5 runtime, otherwise you will get classloading and/or version errors. |
Not enabled |
| Mapping files |
List of additional mapping files that should be loaded. Note: A hibernate.cfg.xml can also contain mappings. Thus if these a duplicated here, you will get "Duplicate mapping" errors when using the console configuration. |
If no hibernate.cfg.xml file is found, all hbm.xml files found in the selected project |
| Classpath |
The classpath for loading POJO and JDBC drivers. Do not add Hibernate core libraries or dependencies, they are already included. If you get ClassNotFound errors then check this list for possible missing or redundant directories/jars. |
The default build output directory and any JARs with a class implementing java.sql.Driver in the selected project |
Clicking "Finish" creates the configuration and shows it in the "Hibernate Configurations" view
3.4. Reverse engineering and code generation
A very simple "click-and-generate" reverse engineering and code generation facility is also available. This facility allows you to generate a range of artifacts based on database or an already existing Hibernate configuration, be that mapping files or annotations. Some of these are POJO Java source file, Hibernate *.hbm.xml, hibernate.cfg.xml generation and even the option for generating the skeleton for a full Seam CRUD application.
To start working with this process, start the "Hibernate Code Generation" which is available in the toolbar via the Hibernate icon or via the "Run/Hibernate Code Generation" menu item.
3.4.1. Code Generation Launcher
When you click on "Hibernate Code Generation" the standard Eclipse launcher dialog will appear. In this dialog you can create, edit and delete named Hibernate code generation "launchers".
The dialog has the standard tabs "Refresh" and "Common" that can be used to configure which directories should be automatically refreshed and various general settings launchers, such as saving them in a project for sharing the launcher within a team.
The first time you create a code generation launcher you should give it a meaningfull name, otherwise the default prefix "New_Generation" will be used.
Note: The "At least one exporter option must be selected" is just a warning stating that for this launch to work you need to select an exporter on the Exporter tab. When an exporter has been selected the warning will disappear.
On the "Main" tab you the following fields:
Table 3.2. Code generation "Main" tab fields
| Field |
Description |
|---|---|
| Console Configuration |
The name of the console configuration which should be used when code generating. |
| Output directory |
Path to a directory into where all output will be written by default. Be aware that existing files will be overwritten, so be sure to specify the correct directory. |
| Reverse engineer from JDBC Connection |
If enabled the tools will reverse engineer the database available via the connection information in the selected Hibernate Console Configuration and generate code based on the database schema. If not enabled the code generation will just be based on the mappings already specified in the Hibernate Console configuration. |
| Package |
The package name here is used as the default package name for any entities found when reverse engineering. |
| reveng.xml |
Path to a reveng.xml file. A reveng.xml file allows you to control certain aspects of the reverse engineering. e.g. how jdbc types are mapped to hibernate types and especially important which tables are included/excluded from the process. Clicking "setup" allows you to select an existing reveng.xml file or create a new one. See more details about the reveng.xml file in Chapter 5, Controlling reverse engineering. |
| reveng. strategy |
If reveng.xml does not provide enough customization you can provide your own implementation of an ReverseEngineeringStrategy. The class need to be in the claspath of the Console Configuration, otherwise you will get class not found exceptions. See Section 5.3, “Custom strategy†for details and an example of a custom strategy. |
| Generate basic typed composite ids |
A table that has a multi-colum primary key a |
| Use custom templates |
If enabled, the Template directory will be searched first when looking up the templates, allowing you to redefine how the individual templates process the hibernate mapping model. |
| Template directory |
A path to a directory with custom templates. |
3.4.2. Exporters
The exporters tab is used to specify which type of code that should be generated. Each selection represents an "Exporter" that are responsible for generating the code, hence the name.
The following table describes in short the various exporters.
Table 3.3. Code generation "Exporter" tab fields
| Field |
Description |
|---|---|
| Generate domain code |
Generates POJO's for all the persistent classes and components found in the given Hibernate configuration. |
| JDK 1.5 constructs |
When enabled the POJO's will use JDK 1.5 constructs. |
| EJB3/JSR-220 annotations |
When enabled the POJO's will be annotated according to the EJB3/JSR-220 persistency specification. |
| Generate DAO code |
Generates a set of DAO's for each entity found. |
| Generate Mappings |
Generate mapping (hbm.xml) files for each entity |
| Generate hibernate configuration file |
Generate a hibernate.cfg.xml file. Used to keep the hibernate.cfg.xml uptodate with any new found mapping files. |
| Generate schema html-documentation |
Generates set of html pages that documents the database schema and some of the mappings. |
| Generate JBoss Seam skeleton app (beta) |
Generates a complete JBoss Seam skeleton app. The generation will include annotated POJO's, Seam controller beans and a JSP for the presentation layer. See the generated readme.txt for how to use it. Note: this exporter generates a full application, including a build.xml thus you will get the best results if you use an output directory which is the root of your project. |
3.5. Hibernate Mapping and Configuration File Editor
The Hibernate Mapping file editor provides XML editing functionality for the hbm.xml and cfg.xml files. The editor is based on the Eclipse WTP tools and extend its functionallity to provide hiberante specific code completion.
3.5.1. Java property/class completion
Package, class, and field completion is enabled for relevant XML attributes. The auto-completion detects it's context and limits the completion for e.g.
This is done via the standard hyperlink navigation functionallity in Eclipse; per default it is done by pressing F3 while the cursor is on a class/field or by pressing Ctrl and the mouse button to perform the same navigation.
For java completion and navigation to work the file needs to reside inside an Eclipse Java project, otherwise no completion will occur. Note: java completion does not require a hibernate console configuration to be used.
3.5.2. Table/Column completion
Table and column completion is also available for all table and column attributes.
Note that it requires a proper configured hibernate console configuration and this configuration should be the default for the project where the hbm.xml resides.
You can check which console configuration is selected under the Properties of a project and look under the "Hibernate Settings" page. When a proper configuration is selected it will be used to fetch the table/column names in the background.
Note: Currently it is not recommended to use this feature on large databases since it does not fetch the information iteratively. It will be improved in future versions.
3.5.3. Configuration property completion
In cfg.xml code completion for the value of
3.6. Reveng.xml editor
A reveng.xml file is used to customize and control how reverse engineering is performed by the tools. The plugins provide and editor to ease the editing of this file and hence used to configure the reverse engineering process.
The editor is intended to allow easy definition of type mappings, table include/excludes and specific override settings for columns, e.g. define a explicit name for a column when the default naming rules is not applicable.
Note that not all the features of the .reveng.xml file is exposed or fully implemented in the editor, but the main functionallity is there. To understand the full flexibility of the reveng.xml, please see
The editor is activated as soon as an .reveng.xml file is opened. To get an initial reveng.xml file the reveng.xml wizard can be started via Ctrl+N or via the code generation launcher.
The following screentshot shows the overview page where the wanted console configuration is selected (auto-detected if Hibernate 3 support is enabled for the project)
The table filter page allows you to specify which tables to include and exclude. Pressing refresh shows the tables from the database that have not yet been excluded.
Type mappings page is used for specifying type mappings from jdbc types to any hibernate type (including usertypes) if the default rules are not applicable.
Table Columns page allow the user to explicit set e.g. which hibernatetype and propertyname that should be used in the reverse engineered model.
3.7. Hibernate Console perspective
The Hibernate Console perspective combines a set of views which allow you to see the structure of your mapped entities/classes, edit HQL queries, execute the queries, and see the results. To use this perspective you need to create a console configuration.
3.7.1. Viewing the entity structure
To view your new configuration and entity/class structure, expand the Hibernate Console configuration by clicking on the + icon.
Clicking on the small + symbol allows you to browse the class/entity structure and see the relationships.
Hibernate Console perspective showing entity structure, query editor and result3.7.1.1. Class Diagram
A class diagram is available in the view named "Hibernate Entity Model". It will show the model for any slected hibernate console configuration.
3.7.2. Prototyping Queries
Queries can be prototyped by entering them in the HQL editor. The HQL Editor is opened by right-clicking the Console configuration and select "HQL Scratchpad".
If the menu item is disabled then you need to first create an SessionFactory. That is done by right clicking the configuration and select "Create Session Factory" or by simpy expanding the Session Factory node.
Executing the query is done by clicking the green run button in the toolbar or pressing Ctrl+Enter.
Errors during creation of the SessionFactory or running the queries (e.g. if your configuration or query is incorrect) will be shown in a message dialog or inlined in the view that detected the error, you may get more information about the error in the Error Log view on the right pane.
Results of a query will be shown in the Query result view and details of possible errors (syntax errors, database errors, etc.) can be seen in the Error Log view.
Tip: HQL queries are executed using list() and without any limit of the size of the output. Be careful if you execute a query on a large result set. You might run out of memory. This will be improved in a future version.
3.7.2.1. Dynamic Query Translator
If the "Hibernate Dynamic Query Translator" view is visible while writing in the HQL editor it will show the generated SQL for a HQL query.
The translation is done each time you stop typing into the editor, if there are an error in the HQL the parse exception will be shown embedded in the view.
3.7.3. Properties view
The properties view shows the structure of any selected persistent object in the results view. Editing is not yet supported.
3.8. Enable debug logging in the plugins
It is possible to configure the eclipse plugin to route all logging made by the plugins and hibernate code it self to the "Error log" view in Eclipse.
This is done by editing the "hibernate-log4j.properties" in org.hibernate.eclipse/ directory/jar. This file includes a default configuration that only logs WARN and above to a set of custom appenders (PluginFileAppender and PluginLogAppender). You can change these settings to be as verbose or silent as you please - see hibernate documentation for interesting categories and log4j documentation for how to configure logging via a log4j property file.
Chapter 4. Ant Tools
4.1. Introduction
The hibernate-tools.jar contains the core for the Hibernate Tools. It is used as the basis for both the Ant tasks described in this document and the eclipse plugins both available from tools.hibernate.org The hibernate-tools.jar is located in your eclipse plugins directory at
/plugins/org.hibernate.eclipse.x.x.x/lib/tools/hibernate-tools.jar
. This jar is 100% independent from the eclipse platform.
4.1.1. The
To use the ant tasks you ned to have the hibernatetool task defined. That is done in your build.xml by inserting the following xml:
This
Notice that to use the annotation based Configuration you must get a release from http://annotations.hibernate.org. When using the
( | | ) ( , ,...*)
| (1) | destdir (requiredl): destination directory for files generated with exporters. |
| (2) | templatepath (optional): A path to be used to look up user-edited templates. |
| (3) | classpath (optional): A classpath to be used to resolve resources, such as mappings and usertypes. Optional, but very often required. |
| (4) | property and propertyset (optional): Used to set properties to control the exporters. Mostly relevant for providing custom properties to user defined templates. |
4.1.2. Hibernate Configurations
hibernatetool supports three different Hibernate configurations: A standard Hibernate configuration (
Each have in common that they are able to build up a Hibernate Configuration object from which a set of exporters can be run to generate various output.
4.1.2.1. Standard Hibernate Configuration ()
A
| (1) | configurationfile (optional): The name of a Hibernate configuration file, e.g. "hibernate.cfg.xml" |
| (2) | propertyfile (optional): The name of a property file, e.g. "hibernate.properties" |
| (3) | entity-resolver (optional): name of a class that implements org.xml.sax.EntityResolver. Used if the mapping files require custom entity resolver. |
| (4) | namingstrategy (optional): name of a class that implements org.hibernate.cfg.NamingStrategy. Used for setting up the naming strategy in Hibernate which controls the automatic naming of tables and columns. |
| (5) | A standard Ant fileset. Used to include hibernate mapping files.Remember that if mappings are already specified in the hibernate.cfg.xml then it should not be included via the fileset as it will result in duplicate import exceptions. |
4.1.2.2. Annotation based Configuration ()
An
The
Thus the minimal usage is:
4.1.2.3. JDBC Configuration for reverse engineering ()
A
...
4.1.3. Code Exporters
Code exporters is the parts that does the actual job of converting the hibernate metamodel into various code artifacts. The following section describes the current supported set of exporters in the Hibernate Tool distribution. It is also possible for userdefined exporters, that is done through the
4.1.3.1. Database schema exporter (
4.1.3.2. POJO java code exporter (
4.1.3.3. Hibernate Mapping files exporter (
4.1.3.4. Hibernate Configuration file exporter (
4.1.3.5. Documentation exporter (
4.1.3.6. Generic Hibernate metamodel exporter (
Generic exporter that can be controlled by a user provided template or class.
NOTICE: This release uses Velocity for the templates. The next release might move to an alternative template engine.
4.1.3.6.1. Seam Exporter via
The following is an example of reverse engineering via
4.1.4. Using properties to configure Exporters
Exporters can be controlled by user properties. The user properties is specificed via
4.1.4.1.
The
Most times using
4.1.4.2. Getting access to user specific classes
If the templates need to access some user class it is possible by specifying a "toolclass" in the properties.
Placing the above
Chapter 5. Controlling reverse engineering
When using the
To govern this process Hibernate uses a reverse engineering strategy. A reverse engineering strategy is mainly called to provide more java like names for tables, column and foreignkeys into classes, properties and associations. It also used to provide mappings from SQL types to Hibernate types. The strategy can be customized by the user. The user can even provide its own custom reverse engineering strategy if the provided strategy is not enough, or simply just provide a small part of the strategy and delegate the rest to the default strategy.
5.1. Default reverse engineering strategy
The default strategy uses some rules for mapping JDBC artifact names to java artifact names. It also provide basic typemappings from JDBC types to Hibernate types. It is the default strategy that uses the packagename attribute to convert a table name to a fully qualified classname.
5.2. hibernate.reveng.xml file
To have fine control over the process a hibernate.reveng.xml file can be provided. In this file you can specify type mappings and table filtering. This file can be created by hand (its just basic XML) or you
can use the Hibernate plugins which have a specialized editor.
The following is an example of such a file.
seq_table
5.2.1. Type mappings ()
The
The number of attributes specificed and the sequence of the sql-type's is important. Meaning that Hibernate will search for the most specific first, and if no specific match is found it will seek from top to bottom when trying to resolve a type mapping.
5.2.1.1. Example
The following is an example of a type-mapping which shows the flexibility and the importance of ordering of the type mappings.
The following table shows how this affects an example table named CUSTOMER:
Table 5.1. Supported meta tags
| Column | jdbc-type | length | precision | not-null | Resulting hibernate-type | Rationale |
|---|---|---|---|---|---|---|
| ID | INTEGER | 10 | true | int | Nothing defined for INTEGER. Falling back to default behavior. | |
| NAME | VARCHAR | 30 | false | your.package.TrimStringUserType | No type-mapping matches length=30 and not-null=false, but type-mapping matches the 2 mappings which only specifies VARCHAR. The type-mapping that comes first is chosen. | |
| INITIAL | VARCHAR | 1 | false | char | Even though there is a generic match for VARCHAR, the more specifc type-mapping for VARCHAR with not-null="false" is chosen. The first VARCHAR sql-type matches in length but has no value for not-null and thus is not considered. | |
| CODE | VARCHAR | 1 | true | java.lang.Character | The most specific VARCHAR with not-null="true" is selected. | |
| SALARY | NUMERIC | 15 | false | big_decimal | There is a precise match for NUMERIC with precision 15 | |
| AGE | NUMERIC | 3 | false | java.lang.Long | type-mapping for NUMERIC with not-null="false" |
5.2.2. Table filters ()
The
5.2.3. Specific table configuration (
5.2.3.1.
parameter value
5.2.3.2.
5.2.3.3.
5.3. Custom strategy
It is possible to implement a user strategy. Such strategy must implement org.hibernate.cfg.reveng.ReverseEngineeringStrategy. It is recommended that one uses the DelegatingReverseEngineeringStrategy and provide a public constructor which takes another ReverseEngineeringStrategy as argument. This will allow you to only implement the relevant methods and provide a fallback strategy. Example of custom delegating strategy which converts all column names that ends with "PK" into a property named "id".
public class ExampleStrategy extends DelegatingReverseEngineeringStrategy {
public ExampleStrategy(ReverseEngineeringStrategy delegate) {
super(delegate);
}
public String columnToPropertyName(TableIdentifier table, String column) {
if(column.endsWith("PK")) {
return "id";
} else {
return super.columnToPropertyName(table, column);
}
}
}
Chapter 6. Controlling POJO code generation
When using
6.1. The attribute
The tag is a simple way of annotating the hbm.xml with information, so tools have a natural place to store/read information that is not directly related to the Hibernate core.
You can use the tag to e.g. tell hbm2java to only generate "protected" setters, have classes always implement a certain set of interfaces or even have them extend a certain base class and even more.
The following example shows how to use various attributes and the resulting java code.
Javadoc for the Person class @author Frodo IAuditable protected The name of the person
The above hbm.xml will produce something like the following (code shortened for better understanding). Notice the Javadoc comment and the protected set methods:
// default package
import java.io.Serializable;
import org.apache.commons.lang.builder.EqualsBuilder;
import org.apache.commons.lang.builder.HashCodeBuilder;
import org.apache.commons.lang.builder.ToStringBuilder;
/**
* Javadoc for the Person class
* @author Frodo
*/
public class Person implements Serializable, IAuditable {
public Long id;
public String name;
public Person(java.lang.String name) {
this.name = name;
}
public Person() {
}
public java.lang.Long getId() {
return this.id;
}
protected void setId(java.lang.Long id) {
this.id = id;
}
/**
* The name of the person
*/
public java.lang.String getName() {
return this.name;
}
public void setName(java.lang.String name) {
this.name = name;
}
}
Table 6.1. Supported meta tags
| Attribute | Description |
|---|---|
| class-description | inserted into the javadoc for classes |
| field-description | inserted into the javadoc for fields/properties |
| interface | If true an interface is generated instead of an class. |
| implements | interface the class should implement |
| extends | class the class should extend (ignored for subclasses) |
| generated-class | overrule the name of the actual class generated |
| scope-class | scope for class |
| scope-set | scope for setter method |
| scope-get | scope for getter method |
| scope-field | scope for actual field |
| default-value | default initializatioin value for a field |
| use-in-tostring | include this property in the toString() |
| use-in-equals | include this property in the equals() and hashCode() method. If no use-in-equals is specificed, no equals/hashcode will be generated. |
| gen-property | property will not be generated if false (use with care) |
| property-type | Overrides the default type of property. Use this with any tag's to specify the concrete type instead of just Object. |
| class-code | Extra code that will inserted at the end of the class |
| extra-import | Extra import that will inserted at the end of all other imports |
Attributes declared via the tag are per default "inherited" inside an hbm.xml file.
What does that mean? It means that if you e.g want to have all your classes implement IAuditable then you just add an IAuditable in the top of the hbm.xml file, just after
Note: This applies to all -tags. Thus it can also e.g. be used to specify that all fields should be declare protected, instead of the default private. This is done by adding protected at e.g. just under the
To avoid having a -tag inherited then you can simply specify inherit="false" for the attribute, e.g. public abstract will restrict the "class-scope" to the current class, not the subclasses.
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