解决Hibernate 3不支持 "&" 运算的SQL语句

where a.id & :mask = :target

package com.js.dialect;

import java.util.List;

import org.hibernate.Hibernate;
import org.hibernate.QueryException;
import org.hibernate.dialect.function.SQLFunction;
import org.hibernate.engine.Mapping;
import org.hibernate.engine.SessionFactoryImplementor;
import org.hibernate.type.Type;

/**
* <p>
* Title:BitAndFunction
* </p>
* <p>
* Description:
* </p>
*
* @author js
* @version
* @since
*/

public class BitAndFunction implements SQLFunction {
public Type getReturnType(Type type, Mapping mapping) {
  return Hibernate.INTEGER;
}

public boolean hasArguments() {
  return true;
}

public boolean hasParenthesesIfNoArguments() {
  return true;
}

public String render(List args, SessionFactoryImplementor factory)
   throws QueryException {
  if (args.size() != 2) {
   throw new IllegalArgumentException(
     "BitAndFunction requires 2 arguments!");
  }
  return args.get(0).toString() + " & " + args.get(1).toString();
}

}

然后，根据使用的数据库方言，派生一个自定义的CustomSQLDialect：

package com.js.dialect;

import org.hibernate.dialect.MySQLInnoDBDialect;

/**
* <p>
* Title:CustomSQLDialect
* </p>
* <p>
* Description:
* </p>
*
* @author js
* @version
* @since
*/
public class CustomSQLDialect extends MySQLInnoDBDialect {
/**
  *
  */
public CustomSQLDialect() {
  super();
  registerFunction("bitand", new BitAndFunction());
}

}

where bitand(a.id, :mask) = :target