7. Attribute Variables

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To access the attribute values of the corresponding tag to your Frame use special attribute variables.

Attribute variables are declared as follows:

public @#attr_type attr_name;

HuGo knows the following attribute types:

Attribute Types

attr_type	Meaning
String	a String like in Java
int	a int like in Java
double	a double like in Java
boolean	a boolean like in Java

Tip

Use the types you need within your Frame class instead of just using @#String for all attributes. Thus you do not need to extract e.g. the integer value out of the string, as in the XML syntax all attribute values are written as strings.

The attr_name is identical to the attribute name you use in the .model file. That means the variable is initialized with the value of the corresponding attribute in the tag, which belongs to the Frame class.

Note

The initializing order is as follows:

1. Initialize with init values at declaration.

2. Initialize with values from the model (if attribute value is specified there)

3. call @#constructor

Caution

The name of an attribute variable is case sensitiv (analog to other Java variables).

Access to variables

The access to the variables value work like the access to other normal variables. If you are inside a generating method use <!...!> to access it.

Example 7.1. Attributes

The following example shows as well how you can handle optional attributes in the .model file.

The people.model

<model>
   <person name="Paul" 
                    age="34"
                    height="1.84"
                    />	
</model>

The person.jxgp

package java_frames;
public class person extends Frame
{
  @@ Attributes
  public @#String name;
  public @#int age;
  public @#double height;
  public @#boolean male=true;   @@ optional attribute
  
  @#gen JCLASS<!name+".java","src","JAVA"!>
   <#java
       public class <!name!> 
       {
         int m_age=<!age!>;
         double m_height=<!height!>;
         boolean m_male=<!male!>;
       }
   #>
}

The generated paul.java

public class Paul 
{
 int m_age=34;
 double m_height=1.84;
 boolean m_male=true;
}