休眠的逆向工程列缺少不为空的属性

Question

I am using hibernate reverse engineering to retrieve entities from DB (in this case oracle DB). I found in some cases constraints not-null is missing in generated hbm files. And it depends how table(column) is created(defined).

This is ok:

CREATE TABLE "MY_TABLE1"
(
...
"RECORD_CREATED" DATE DEFAULT SYSDATE NOT NULL ENABLE,
...

Then in hbm file we got for this column record:

<column length="7" name="RECORD_CREATED" not-null="true"></column>

This in not ok:

CREATE TABLE "MY_TABLE1"
(
...
  "RECORD_CREATED" DATE DEFAULT SYSDATE,
  ...
  ...
  CHECK ("RECORD_CREATED" IS NOT NULL) ENABLE,
  ...

Then in hbm file we got for this column record:

<column length="7" name="RECORD_CREATED"></column>

I don't understand why it is so, why hibernate is so sensitive to that? Maybe is just matter of configuration, but I was not able found something related to that.

What is the problem? Why in second case I missing "not-null=true" attribute ?

Thanks

Answer 1

Write your own Strategy.

Refere it in maven like this:

<build><plugins><plugin>
    <artifactId>hibernate3-maven-plugin</artifactId>
    <configuration>
      <components>
        <component>
          <name>hbm2java</name>
        </component>
      </components>
      <reversestrategy>MyStrategyImpl</reversestrategy>
         ...

And write it like this:

public class MyStrategyImpl extends DelegatingReverseEngineeringStrategy {
    public String columnToHibernateTypeName(TableIdentifier table, String columnName, int sqlType, int length, int precision, int scale, boolean nullable, boolean generatedIdentifier) {
      if(/*yourJdbcSelects*/){
        nullable = true;
      }
      super.columnToHibernateTypeName(table, columnName, sqlType, length, precision, scale, nullable, generatedIdentifier);
    }
}