Thanks in advance for the help..

Running the latest Hibernate version (2.1 beta) and I'm receiving the following error when attempting to create a Configuration

&*&*&*&*&*&*&*&
SEVERE: Could not compile the mapping document
net.sf.hibernate.PropertyNotFoundException: Could not find a getter for null in class mtmdemo.Permission
at net.sf.hibernate.util.ReflectHelper.getGetter(ReflectHelper.java:206)
*&*&*&*&*&*&*&*&

Here is the code: - if I just run the statement w/ the User class it works just fine.
Transaction tx = null;

Configuration ds = new Configuration().addClass(Permission.class)
.addClass(User.class);

Here is the code for the Permission and User Classes

/**
* Class that represents a permission.
*
*/
public class Permission {

private double id;
private String name;
private Set users = new HashSet();


public Permission() {
super();
// TODO Auto-generated constructor stub
}


/**
* ID accessors
*/
public double getId() {
return id;
}
public void setId(double iD) {
id = iD;
}

/**
* Name accessors
*/
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}

/**
* User accessors
*/
public Set getUsers() {
return users;
}
public void setUsers(Set users) {
this.users = users;
}
public void addUser(User user){
users.add(user);
}
public void removeUser(User user){
users.remove(user);
}

}


/**
* Class that represents a user.
*
*/
public class User {

private double id;
private String name;
private Set permissions = new HashSet();

public User() {
super();
// TODO Auto-generated constructor stub
}

/**
* ID accessors
*/
public double getId() {
return id;
}
public void setId(double iD) {
id = iD;
}

/**
* Name accessors
*/
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}

/**
* Permission accessors
*/
public Set getPermissions() {
return permissions;
}
public void setPermissions(Set permissions) {
this.permissions = permissions;
}
public void addPermission(Permission permission){
permissions.add(permission);
}
public void removePermission(Permission permission){
permissions.remove(permission);
}

}

*** And here are the mappings for Permission and User
*** Permission Mapping
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD//EN"
"http://hibernate.sourceforge.net/hibernate-mapping.dtd">

<hibernate-mapping>
<class name="mtmdemo.Permission" table="permissions">
<id name="id" type="long" column="permissionid">
<generator class="native"/>
</id>
<property name="name" column="permissionname" not-null="true"/>
<set role="users" table="userpermissions" readonly="true" lazy="true">
<key column="permissionid"/>
<many-to-many class="mtmdemo.User" column="userid"/>
</set>
</class>
</hibernate-mapping>

*** User Mapping
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD//EN"
"http://hibernate.sourceforge.net/hibernate-mapping.dtd">

<hibernate-mapping>
<class name="mtmdemo.User" table="users">
<id name="id" column="userid" not-null="true">
<generator class="native"/>
</id>
<property name="name" column="username" unique="false" not-null="true" />
<set name="permissions" table="userpermissions" lazy="true">
<key column="userid"/>
<many-to-many class="mtmdemo.Permission" column="permissionid"/>
</set>
</class>
</hibernate-mapping>


net.sf.hibernate.MappingException: Problem trying to set property type by reflection: Could not find a getter for null in class mtmdemo.Permission

You are mixing 1X and 2X mapping syntax. Change the Permission mapping for the user set to:


Note:
role -> name
readonly -> inverse

You had it correct on the User's set mapping...

Still does not work.. now I get :

org.xml.sax.SAXParseException: Attribute "inverse" is not declared for element "set".
at org.apache.crimson.parser.Parser2.error(Parser2.java:3317)
at org.apache.crimson.parser.Parser2.maybeElement(Parser2.java:1558)
.
.
.
org.xml.sax.SAXParseException: Attribute value for "role" is #REQUIRED.
at org.apache.crimson.parser.Parser2.error(Parser2.java:3317)


I tried putting role back and removing inverse to no avail..

In your mapping see how you have:
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD//EN"
"http://hibernate.sourceforge.net/hibernate-mapping.dtd">

Change this to:
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">

And change role->name; readonly->inverse

For the SAXParseException, try using <bag> instead of <set>. I found these much easier to work with.

One of mine is like this:

<bag name="Child" cascade="all" inverse="true" lazy ="false">
<key column="ParentID" />
<one-to-many class="my.package.impl.ChildImpl" />
</bag>

----------------------------------------------------------------------------
I have my lazy set to false, as my database calls can take a while, so best to grab in one call, as I generally always process the entire structure.

-G

And oh yes, do as Steve says...about the mapping bit. :)

-G

That fixed it!..
I appreciate the help! Great Forum!