The Virtual Reality Modeling Language

Appendix C. Java Scripting Reference

Version 2.0, ISO/IEC CD 14772

December 2, 1996

This annex describes the Java classes and methods that allow Script nodes (see "Nodes Reference - Script") to interact with associated scenes. See "Concepts - Scripting" for a general description of scripting languages in VRML.

C.1 Language

C.2 Supported Protocol in the Script Node's url Field

C.2.1 File Extension

C.2.2 MIME Type

C.3 EventIn Handling

C.3.1 Parameter Passing and the EventIn Field/Method

C.3.2 processEvents() and processEvent() Methods

C.3.3 eventsProcessed() Method

C.3.4 shutdown() Method

C.3.5 initialize() Method

C.4 Accessing Fields and Events

C.4.1 Accessing Fields and EventOuts of the Script

C.4.2 Accessing Fields and EventOuts of Other Nodes

C.4.3 Sending EventOuts

C.5 Exposed Classes and Methods for Nodes and Fields

C.5.1 Field Class and ConstField Class

C.5.2 Node Class

C.5.3 Browser Class

C.5.4 User-defined Classes and Packages

C.5.5 Standard Java Packages

C.6 Exceptions

C.7 Example

C.8 Class Definitions

C.8.1 Class Hierarchy

C.8.2 VRML Packages

C.8.2.1 vrml Package
C.8.2.2 vrml.field Package
C.8.2.3 vrml.node Package

C.9 Example of Exception Class

C.1 Language

Java(TM) is an object-oriented, platform-independent, multi-threaded, general-purpose programming environment developed at Sun Microsystems, Inc. See the Java web site for a full description of the Java programming language (http://java.sun.com/). This appendix describes the Java bindings of VRML to the Script node.

C.2 Supported Protocol in the Script Node's url Field

The url field of the Script node contains the URL of a file containing the Java byte code, for example:

     Script { 
         url "http://foo.co.jp/Example.class"
         eventIn SFBool start
     }

C.2.1 File Extension

The file extension for Java byte code is .class.

C.2.2 MIME Type

The MIME type for Java byte code is defined as follows:

        application/x-java

C.3 EventIn Handling

Events to the Script node are passed to the corresponding Java method (processEvent or processEvents) in the script. It is necessary to specify the script in the url field of the Script node.

If a Java byte code file is specified in the url field, the following three conditions must hold:

For example, the following Script node has one eventIn field whose name is 'start'.

    Script { 
           url "http://foo.co.jp/Example.class"
           eventIn SFBool start
    }

This node points to the script file 'Example.class' - its source ('Example.java') looks like this:

    import vrml.*;
    import vrml.field.*;
    import vrml.node.*;

    public class Example extends Script {
        ...
        // This method is called when any event is received
        public void processEvent (Event e) {
           // ... perform some operation ...
        }
    }

In the above example, when the start eventIn is sent the processEvent() method is executed and receives the eventIn.

C.3.1 Parameter Passing and the EventIn Field/Method

When a Script node receives an eventIn, a processEvent() or processEvents() method in the file specified in url field of the Script node is called, which receives the eventIn as Java objects (Event object). See "processEvent() or processEvents() Method".

The Event object has three information associated with it: name, value and timestamp of the eventIn. These can be retrieved using the corresponding method on the Event object.

   public class Event implements Cloneable {
      public String getName();
      public ConstField getValue();
      public double getTimeStamp();
      // other methods
   }

Suppose that the eventIn type is SFXXX and eventIn name is eventInYYY, then

In the above example, the eventIn name would be "start" and eventIn value could be casted to be ConstSFBool. Also, the timestamp for the time when the eventIn was occurred is available as a double. These are passed as an Event object to processEvent() method:

        public void processEvent (Event e) {
            if(e.getName().equals("start")){
                  ConstSFBool v = (ConstSFBool)e.getValue();
                  if(v.getValue()==true){
                       // ... perform some operation ...
                  }
             }
        }

C.3.2 processEvents() and processEvent() Method

Authors can define a processEvents method within a class that is called when the script receives some set of events. The prototype of processEvents method is

    public void processEvents(int count, Event events[]);

count indicates the number of events delivered. events is the array of events delivered. Its default behavior is to iterate over each event, calling processEvent() on each one as follows:

    public void processEvents(int count, Event events[])
    {
        for (int i = 0; i < count; i++) {
            processEvent( events[i] );
        }
    }

Although authors could change this operation by giving a user-defined processEvents() method, in most cases, they would only change processEvent() method and eventsProcessed() method described below.

When multiple eventIns are routed from single node to single script node and then the eventIns which have the same timestamp are occurred, the processEvents() receives multiple events as the event array. Otherwise, each coming event invokes separate processEvents().

For example, processEvents() method receives two events in the following case :

    Transform {
        children [
            DEF TS TouchSensor {}
            Shape { geometry Cone {} }
        ]
    }
    DEF SC Script {
        url     "Example.class"
        eventIn SFBool isActive
        eventIn SFTime touchTime
    }
    ROUTE TS.isActive  TO SC.isActive
    ROUTE TS.touchTime TO SC.touchTime

Authors can define a processEvent method within a class. The prototype of processEvent is

    public void processEvent(Event event);

Its default behavior is no operation.

C.3.3 eventsProcessed() Method

Authors can define an eventsProcessed method within a class that is called after some set of events has been received. It allows Scripts that do not rely on the ordering of events received to generate fewer events than an equivalent Script that generates events whenever events are received. It is called after every invocation of processEvents().

Events generated from an eventsProcessed routine are given the timestamp of the last event processed.

The prototype of eventsProcessed method is

    public void eventsProcessed();

Its default behavior is no operation.

C.3.4 shutdown() Method

Authors can define a shutdown method within a class that is called when the corresponding Script node is deleted.

The prototype of shutdown method is

    public void shutdown();

Its default behavior is no operation.

C.3.5 initialize() Method

Authors can define an initialize method within a class that is called before any event is generated. The various methods on Script such as getEventIn, getEventOut, getExposedField, and getField are not guaranteed to return correct values before the call to initialize (i.e. in the constructor). initialize() is called once during the life of Script object.

The prototype of initialize method is

    public void initialize();

Its default behavior is no operation.

C.4 Accessing Fields and Events

The fields, eventIns and eventOuts of a Script node are accessible from their corresponding Java classes.

C.4.1 Accessing Fields, EventIns and EventOuts of the Script

Each field defined in the Script node is available to the script by using its name. Its value can be read or written. This value is persistent across function calls. EventOuts defined in the script node can also be read.

Accessing fields of Script node can be done by using Script class methods. Script class has several methods to do that: getField(), getEventOut() and getEventIn().

When you call setValue(), set1Value(), addValue() or insertValue() method on a 'field' object obtained by getField() method, the value specified as an argument is stored in the corresponding VRML node's field.

When you call setValue(), set1Value(), addValue() or insertValue() method on a 'field' object obtained by getEventOut() method, the value specified as an argument generates an event in VRML scene. The effect of this event is specified by the associated Route in the VRML scene.

When you call setValue(), set1Value(), addValue() or insertValue() method on a 'field' object obtained by getEventIn() method, the value specified an argument generates an event to the Script node. For example, the following Script node defines an eventIn, start, a field, state, and an eventOut, on. The method initialize() is invoked before any events are received, and the method processEvent() is invoked when start receives an event:

    Script {
        url       "Example.class"
        eventIn   SFBool start
        eventOut  SFBool on
        field     SFBool state TRUE
    }


  Example.class:

    import vrml.*;
    import vrml.field.*;
    import vrml.node.*;

    public class Example extends Script {
       private SFBool state;
       private SFBool on;

       public void initialize(){
            state = (SFBool) getField("state");
            on = (SFBool) getEventOut("on");
        }

        public void processEvent(Event e) {
            if(state.getValue()==true){
                on.setValue(true); // set true to eventOut 'on'
                state.setValue(false);
            }
            else {
                on.setValue(false); // set false to eventOut 'on'
                state.setValue(true);
            }
        }
    }

C.4.2 Accessing Fields, EventIns and EventOuts of Other Nodes

If a script program has an access to any node, any eventIn, eventOut or exposedField of that node is accessible by using the getEventIn(), getEventOut() or getExposedField() method defined on the node's class (see "Exposed Classes and Methods for Nodes and Fields" ).

The typical way for a script program to have an access to another VRML node is to have an SFNode field which provides a reference to the other node. The following example shows how this is done:

    DEF SomeNode Transform { }
    Script {
         field SFNode node USE SomeNode
         eventIn SFVec3f pos
         url "Example.class"
    }


Example.class:

    import vrml.*;
    import vrml.field.*;
    import vrml.node.*;

    public class Example extends Script {
        private SFNode node;
        private SFVec3f trans;

        public void initialize(){
            node = (SFNode) getField("node");
        }

        public void processEvent(Event e) {
            // gets the ref to 'translation' field of Transform node
            trans = (SFVec3f)((Node) node.getValue()).getExposedField("translation");
            trans.setValue((ConstSFVec3f)e.getValue());
        }
    }

C.4.3 Sending EventIns or EventOuts

Sending eventOuts from script is done by setting value to the reference to the 'eventOut' of the script by setValue(), set1Value(), addValue() or insertValue() method. Sending eventIns from script is done by setting value to the reference to the 'eventIn' by setValue(), set1Value(), addValue() or insertValue() method.

C.5 Exposed Classes and Methods for Nodes and Fields

Java classes for VRML are defined in the packages: vrml, vrml.node and vrml.field.

The Field class extends Java's Object class by default; thus, Field has the full functionality of the Object class, including the getClass() method. The rest of the package defines a "Const" read-only class for each VRML field type, with a getValue() method for each class; and another read/write class for each VRML field type, with both getValue() and setValue() methods for each class. A getValue() method converts a VRML-type value into a Java-type value. A setValue() method converts a Java-type value into a VRML-type value and sets it to the VRML field.

Most of the setValue() methods and set1Value() methods are listed as "throws exception," meaning that errors are possible -- you may need to write exception handlers (using Java's catch() method) when you use those methods. Any method not listed as "throws exception" is guaranteed to generate no exceptions. Each method that throws an exception includes a prototype showing which exception(s) can be thrown.

C.5.1 Field Class and ConstField Class

All VRML data types have equivalent classes in Java. Field class is the root of each field types.

    public abstract class Field implements Cloneable {
        // methods
    }

This class has two subclasses : read-only class and writable class

The Java Field class and its subclasses have several methods to get and set values: getSize(), getValue(), get1Value(), setValue(), set1Value(), addValue(), insertValue(), clear(), delete() or toString().

NOTE: All instances which are typed as the BaseNode class must be an instance of the class which extends the BaseNode class. The concrete class is implementation dependent and up to browser implementation.

In these methods, getSize(), get1Value(), set1Value(), addValue(), insertValue(), clear() and delete() are only available for multiple value field classes(MF classes). See "vrml Package" for each classes' methods definition.

Some constructors and methods of the field classes take an array as an argument.

The following describes how arrays are interpreted in detail. Suppose NA represents the number of elements in the array, and NT represents the number of elements which the target object requires or has. For example, the target object is SFColor, it requires or has exactly 3 float values.

In the following description, suppose SF* represents subclasses of Field class, ConstSF* represents subclasses of ConstField class, MF* represents subclasses of MField class and ConstMF* represents subclasses of ConstMField class.

C.5.2 Node Class

Node class has several methods: getType(), getEventOut(), getEventIn(), getExposedField(), getBrowser() and toString().

When you call setValue(), set1Value(), addValue() or insertValue() method on a 'field' object obtained by getEventIn() method, the value specified as an argument generates an event to the node.

When you call setValue(), set1Value(), addValue() or insertValue() method on a 'field' object obtained by getExposedField() method, the value specified as an argument generates an event in VRML scene. The effect of this event is specified by the associated Route in the VRML scene.

C.5.3 Browser Class

This section lists the public Java interfaces to the Browser class, which allows scripts to get and set browser information. For descriptions of the following methods see the "Concepts - Scripting - Browser Interface".

Return value

Method name

String getName()
String getVersion()
float getCurrentSpeed()
float getCurrentFrameRate()
String getWorldURL()
void replaceWorld(BaseNode[] nodes)
BaseNode[] createVrmlFromString(String vrmlSyntax)
void createVrmlFromURL(String[] url, BaseNode node, String event)
void addRoute(BaseNode fromNode, String fromEventOut, BaseNode toNode, String toEventIn)
void deleteRoute(BaseNode fromNode, String fromEventOut, BaseNode toNode, String toEventIn)
void loadURL(String[] url, String[] parameter)
void setDescription(String description)

See "vrml Package"for each method's definition.

NOTE: All instances which are typed as the BaseNode class must be an instance of the class which extends the BaseNode class. The concrete class is implementation dependent and up to browser implementation.

Conversion table from the types used in Browser class to Java type.

VRML type Java type
SFString String
SFFloat float
MFString String[]
MFNode BaseNode[]

When a relative URL is specified as an argument of loadURL() and createVrmlFromUrl(), the path is relative to the VRML file that contains the Script node.

C.5.4 User-defined Classes and Packages

The Java classes defined by a user can be used in the Java program. They are searched from the directories specified in CLASSPATH environment variable and then the directory where the Java program is placed.

If the Java class is in a package, this package is searched from the directories specified in CLASSPATH environment variable and then the directory where the Java program is placed.

C.5.5 Standard Java Packages

Java programs have access to the full set of classes available in java.*. The security model will be browser specific. Threads are required to work as normal for Java.

C.6 Exceptions

Java methods may throw the following exceptions:

If exceptions are not redefined by authors, a browser's behavior is unspecified - see "Example of Exception Class".

C.7 Example

Here's an example of a Script node which determines whether a given color contains a lot of red. The Script node exposes a color field, an eventIn, and an eventOut:

Script {
    field    SFColor currentColor 0 0 0
    eventIn  SFColor colorIn
    eventOut SFBool  isRed
    url "ExampleScript.class"
}

And here's the source code for the "ExampleScript.java" file that gets called every time an eventIn is routed to the above Script node:

import vrml.*;
import vrml.field.*;
import vrml.node.*;

public class ExampleScript extends Script {
    // Declare field(s)
    private SFColor currentColor;
  
    // Declare eventOut field(s)
    private SFBool isRed;

    // buffer for  SFColor.getValue().
    private float colorBuff[] = new float[3];

    public void initialize(){
       currentColor = (SFColor) getField("currentColor");
       isRed = (SFBool) getEventOut("isRed");
    }
  
    public void processEvent(Event e){
        // This method is called when a colorIn event is received
        currentColor.setValue((ConstSFColor)e.getValue());
    }
  
    public void eventsProcessed() {
        currentColor.getValue(colorBuff);
        if (colorBuff[0] >= 0.5) // if red is at or above 50%
            isRed.setValue(true);
    }
}

For details on when the methods defined in ExampleScript are called - see "Concepts -Execution Model".

Browser class examples:

C.8 Class Definitions

C.8.1 Class Hierarchy

The classes are divided into three packages: vrml, vrml.field and vrml.node.

java.lang.Object
     |
     +- vrml.Event
     +- vrml.Browser
     +- vrml.Field
     |       +- vrml.field.SFBool
     |       +- vrml.field.SFColor
     |       +- vrml.field.SFFloat
     |       +- vrml.field.SFImage
     |       +- vrml.field.SFInt32
     |       +- vrml.field.SFNode
     |       +- vrml.field.SFRotation
     |       +- vrml.field.SFString
     |       +- vrml.field.SFTime
     |       +- vrml.field.SFVec2f
     |       +- vrml.field.SFVec3f
     |       |
     |       +- vrml.MField
     |       |       +- vrml.field.MFColor
     |       |       +- vrml.field.MFFloat
     |       |       +- vrml.field.MFInt32
     |       |       +- vrml.field.MFNode
     |       |       +- vrml.field.MFRotation
     |       |       +- vrml.field.MFString
     |       |       +- vrml.field.MFTime
     |       |       +- vrml.field.MFVec2f
     |       |       +- vrml.field.MFVec3f
     |       |
     |       +- vrml.ConstField
     |               +- vrml.field.ConstSFBool
     |               +- vrml.field.ConstSFColor
     |               +- vrml.field.ConstSFFloat
     |               +- vrml.field.ConstSFImage
     |               +- vrml.field.ConstSFInt32
     |               +- vrml.field.ConstSFNode
     |               +- vrml.field.ConstSFRotation
     |               +- vrml.field.ConstSFString
     |               +- vrml.field.ConstSFTime
     |               +- vrml.field.ConstSFVec2f
     |               +- vrml.field.ConstSFVec3f
     |               |
     |               +- vrml.ConstMField
     |                       +- vrml.field.ConstMFColor
     |                       +- vrml.field.ConstMFFloat
     |                       +- vrml.field.ConstMFInt32
     |                       +- vrml.field.ConstMFNode
     |                       +- vrml.field.ConstMFRotation
     |                       +- vrml.field.ConstMFString
     |                       +- vrml.field.ConstMFTime
     |                       +- vrml.field.ConstMFVec2f
     |                       +- vrml.field.ConstMFVec3f
     |
     +- vrml.BaseNode
             +- vrml.node.Node
             +- vrml.node.Script

java.lang.Exception
        java.lang.RuntimeException
                vrml.InvalidRouteException
                vrml.InvalidFieldException
                vrml.InvalidEventInException
                vrml.InvalidEventOutException
                vrml.InvalidExposedFieldException
                vrml.InvalidFieldChangeException
                vrml.InvalidVRMLSyntaxException

C.8.2 vrml Packages

C.8.2.1 vrml Package

package vrml;

public abstract class Field implements Cloneable
{
   public Object clone();
}

public abstract class ConstField extends Field
{
}

public abstract class ConstMField extends ConstField
{
   public abstract int getSize();
}

public abstract class MField extends Field
{
   public abstract int getSize();
   public abstract void clear();
   public abstract void delete(int index);
}

public class Event implements Cloneable {
  public String getName();
  public double getTimeStamp();
  public ConstField getValue();
  public Object clone();
  // This overrides a method in Object
  public String toString();
}

public class Browser {
  private Browser();
  // This overrides a method in Object
  public String toString();

  // Browser interface
  public String getName();    
  public String getVersion();    

  public float getCurrentSpeed();

  public float getCurrentFrameRate();

  public String getWorldURL();
  public void replaceWorld(BaseNode[] nodes);

  public BaseNode[] createVrmlFromString(String vrmlSyntax)
    throws InvalidVRMLSyntaxException;

  public void createVrmlFromURL(String[] url, BaseNode node, String event)

  public void addRoute(BaseNode fromNode, String fromEventOut,
    BaseNode toNode, String toEventIn);

  public void deleteRoute(BaseNode fromNode, String fromEventOut,
    BaseNode toNode, String toEventIn);

  public void loadURL(String[] url, String[] parameter)

  public void setDescription(String description);
}

//
// This is the general BaseNode class
// 
public abstract class BaseNode 
{
  // Returns the type of the node.  If the node is a prototype
  //   it returns the name of the prototype.
  public String getType();

  // Get the Browser that this node is contained in.
  public Browser getBrowser();
}

C.8.2.2 vrml.field Package

package vrml.field;

public class ConstSFBool extends ConstField
{
   public ConstSFBool(boolean value);
   public boolean getValue();
   // This overrides a method in Object
   public String toString();
}

public class ConstSFColor extends ConstField
{
   public ConstSFColor(float red, float green, float blue);
   public void getValue(float colors[]);
   public float getRed();
   public float getGreen();
   public float getBlue();
   // This overrides a method in Object
   public String toString();
}

public class ConstSFFloat extends ConstField
{
   public ConstSFFloat(float value);
   public float getValue();
   // This overrides a method in Object
   public String toString();
}

public class ConstSFImage extends ConstField
{
   public ConstSFImage(int width, int height, int components, byte pixels[]);
   public int getWidth();
   public int getHeight();
   public int getComponents();
   public void getPixels(byte pixels[]);
   // This overrides a method in Object
   public String toString();
}

public class ConstSFInt32 extends ConstField
{
   public ConstSFInt32(int value);
   public int getValue();
   // This overrides a method in Object
   public String toString();
}

public class ConstSFNode extends ConstField
{
   public ConstSFNode(BaseNode node);
   public BaseNode getValue();
   // This overrides a method in Object
   public String toString();
}

public class ConstSFRotation extends ConstField
{
   public ConstSFRotation(loat axisX, float axisY, float axisZ, float angle);
   public void getValue(float rotations[]);
   // This overrides a method in Object
   public String toString();
}

public class ConstSFString extends ConstField
{
   public ConstSFString(String value)
   public String getValue();
   // This overrides a method in Object
   public String toString();
}

public class ConstSFTime extends ConstField
{
   public ConstSFTime(double time);
   public double getValue();
   // This overrides a method in Object
   public String toString();
}

public class ConstSFVec2f extends ConstField
{
   public ConstSFVec2f(float x, float y);
   public void getValue(float vec2s[]);
   public float getX();
   public float getY();
   // This overrides a method in Object
   public String toString();
}

public class ConstSFVec3f extends ConstField
{
   public ConstSFVec3f(float x, float y, float z);
   public void getValue(float vec3s[]);
   public float getX();
   public float getY();
   public float getZ();
   // This overrides a method in Object
   public String toString();
}

public class ConstMFColor extends ConstMField
{
   public ConstMFColor(float colors[][]);
   public ConstMFColor(float colors[]);
   public ConstMFColor(int size, float colors[]);

   public void getValue(float colors[][]);
   public void getValue(float colors[]);
   public void get1Value(int index, float colors[]);
   public void get1Value(int index, SFColor color);
   // This overrides a method in Object
   public String toString();
}

public class ConstMFFloat extends ConstMField
{
   public ConstMFFloat(int size, float values[]);
   public ConstMFFloat(float values[]);

   public void getValue(float values[]);
   public float get1Value(int index);
   // This overrides a method in Object
   public String toString();
}

public class ConstMFInt32 extends ConstMField
{
   public ConstMFInt32(int size, int values[]);
   public ConstMFInt32(int values[]);

   public void getValue(int values[]);
   public int get1Value(int index);
   // This overrides a method in Object
   public String toString();
}

public class ConstMFNode extends ConstMField
{
   public ConstMFNode(int size, BaseNode node[]);
   public ConstMFNode(BaseNode node[]);

   public void getValue(BaseNode node[]);
   public BaseNode get1Value(int index);
   // This overrides a method in Object
   public String toString();
}

public class ConstMFRotation extends ConstMField
{
   public ConstMFRotation(float rotations[][]);
   public ConstMFRotation(float rotations[]);
   public ConstMFRotation(int size, float rotations[]);

   public void getValue(float rotations[][]);
   public void getValue(float rotations[]);
   public void get1Value(int index, float rotations[]);
   public void get1Value(int index, SFRotation rotation);
   // This overrides a method in Object
   public String toString();
}

public class ConstMFString extends ConstMField
{
   public ConstMFString(int size, String s[]);
   public ConstMFString(String s[]);

   public void getValue(String values[]);
   public String get1Value(int index);
   // This overrides a method in Object
   public String toString();
}

public class ConstMFTime extends ConstMField
{
   public ConstMFTime(int size, double times[]);
   public ConstMFTime(double times[]);

   public void getValue(double times[]);
   public double get1Value(int index);
   // This overrides a method in Object
   public String toString();
}

public class ConstMFVec2f extends ConstMField
{
   public ConstMFVec2f(float vec2s[][]);
   public ConstMFVec2f(float vec2s[]);
   public ConstMFVec2f(int size, float vec2s[]);

   public void getValue(float vec2s[][]);
   public void getValue(float vec2s[]);
   public void get1Value(int index, float vec2s[]);
   public void get1Value(int index, SFVec2f vec);
   // This overrides a method in Object
   public String toString();
}

public class ConstMFVec3f extends ConstMField
{
   public ConstMFVec3f(float vec3s[][]);
   public ConstMFVec3f(float vec3s[]);
   public ConstMFVec3f(int size, float vec3s[]);

   public void getValue(float vec3s[][]);
   public void getValue(float vec3s[]);
   public void get1Value(int index, float vec3s[]);
   public void get1Value(int index, SFVec3f vec);
   // This overrides a method in Object
   public String toString();
}

public class SFBool extends Field
{
   public SFBool();
   public SFBool(boolean value);
   public boolean getValue();
   public void setValue(boolean b);
   public void setValue(ConstSFBool b);
   public void setValue(SFBool b);
   // This overrides a method in Object
   public String toString();
}

public class SFColor extends Field
{
   public SFColor();
   public SFColor(float red, float green, float blue);
   public void getValue(float colors[]);
   public float getRed();
   public float getGreen();
   public float getBlue();
   public void setValue(float colors[]);
   public void setValue(float red, float green, float blue);
   public void setValue(ConstSFColor color);
   public void setValue(SFColor color);
   // This overrides a method in Object
   public String toString();
}

public class SFFloat extends Field
{
   public SFFloat();
   public SFFloat(float f);
   public float getValue();
   public void setValue(float f);
   public void setValue(ConstSFFloat f);
   public void setValue(SFFloat f);
   // This overrides a method in Object
   public String toString();
}

public class SFImage extends Field
{
   public SFImage();
   public SFImage(int width, int height, int components, byte pixels[]);
   public int getWidth();
   public int getHeight();
   public int getComponents();
   public void getPixels(byte pixels[]);
   public void setValue(int width, int height, int components,
                        byte pixels[]);
   public void setValue(ConstSFImage image);
   public void setValue(SFImage image);
   // This overrides a method in Object
   public String toString();
}

public class SFInt32 extends Field
{
   public SFInt32();
   public SFInt32(int value);
   public int getValue();
   public void setValue(int i);
   public void setValue(ConstSFInt32 i);
   public void setValue(SFInt32 i);
   // This overrides a method in Object
   public String toString();
}

public class SFNode extends Field
{
   public SFNode();
   public SFNode(BaseNode node);

   public BaseNode getValue();
   public void setValue(BaseNode node);
   public void setValue(ConstSFNode node);
   public void setValue(SFNode node);
   // This overrides a method in Object
   public String toString();
}

public class SFRotation extends Field
{
   public SFRotation();
   public SFRotation(float axisX, float axisY, float axisZ, float angle);
   public void getValue(float rotations[]);
   public void setValue(float rotations[]);
   public void setValue(float axisX, float axisY, float axisZ, float angle);
   public void setValue(ConstSFRotation rotation);
   public void setValue(SFRotation rotation);
   // This overrides a method in Object
   public String toString();
}

public class SFString extends Field
{
   public SFString();
   public SFString(String s);
   public String getValue();
   public void setValue(String s);
   public void setValue(ConstSFString s);
   public void setValue(SFString s);
   // This overrides a method in Object
   public String toString();
}

public class SFTime extends Field
{
   public SFTime();
   public SFTime(double time);
   public double getValue();
   public void setValue(double time);
   public void setValue(ConstSFTime time);
   public void setValue(SFTime time);
   // This overrides a method in Object
   public String toString();
}

public class SFVec2f extends Field
{
   public SFVec2f();
   public SFVec2f(float x, float y);
   public void getValue(float vec2s[]);
   public float getX();
   public float getY();
   public void setValue(float vec2s[]);
   public void setValue(float x, float y);
   public void setValue(ConstSFVec2f vec);
   public void setValue(SFVec2f vec);
   // This overrides a method in Object
   public String toString();
}

public class SFVec3f extends Field
{
   public SFVec3f();
   public SFVec3f(float x, float y, float z);
   public void getValue(float vec3s[]);
   public float getX();
   public float getY();
   public float getZ();
   public void setValue(float vec3s[]);
   public void setValue(float x, float y, float z);
   public void setValue(ConstSFVec3f vec);
   public void setValue(SFVec3f vec);
   // This overrides a method in Object
   public String toString();
}

public class MFColor extends MField
{
   public MFColor();
   public MFColor(float colors[][]);
   public MFColor(float colors[]);
   public MFColor(int size, float colors[]);

   public void getValue(float colors[][]);
   public void getValue(float colors[]);

   public void setValue(float colors[][]);
   public void setValue(float colors[]);
   public void setValue(int size, float colors[]);
   /****************************************************
    color[0] ... color[size - 1] are used as color data
    in the way that color[0], color[1], and color[2] 
    represent the first color. The number of colors
    is defined as "size / 3".
    ***************************************************/
   public void setValue(MFColor colors);
   public void setValue(ConstMFColor colors);

   public void get1Value(int index, float colors[]);
   public void get1Value(int index, SFColor color);

   public void set1Value(int index, ConstSFColor color);
   public void set1Value(int index, SFColor color);
   public void set1Value(int index, float red, float green, float blue);

   public void addValue(ConstSFColor color);
   public void addValue(SFColor color);
   public void addValue(float red, float green, float blue);

   public void insertValue(int index, ConstSFColor color);
   public void insertValue(int index, SFColor color);
   public void insertValue(int index, float red, float green, float blue);
   // This overrides a method in Object
   public String toString();
}

public class MFFloat extends MField
{
   public MFFloat();
   public MFFloat(int size, float values[]);
   public MFFloat(float values[]);

   public void getValue(float values[]);

   public void setValue(float values[]);
   public void setValue(int size, float values[]);
   public void setValue(MFFloat value);
   public void setValue(ConstMFFloat value);

   public float get1Value(int index);

   public void set1Value(int index, float f);
   public void set1Value(int index, ConstSFFloat f);
   public void set1Value(int index, SFFloat f);

   public void addValue(float f);
   public void addValue(ConstSFFloat f);
   public void addValue(SFFloat f);

   public void insertValue(int index, float f);
   public void insertValue(int index, ConstSFFloat f);
   public void insertValue(int index, SFFloat f);
   // This overrides a method in Object
   public String toString();
}

public class MFInt32 extends MField
{
   public MFInt32();
   public MFInt32(int size, int values[]);
   public MFInt32(int values[]);

   public void getValue(int values[]);

   public void setValue(int values[]);
   public void setValue(int size, int values[]);
   public void setValue(MFInt32 value);
   public void setValue(ConstMFInt32 value);

   public int get1Value(int index);

   public void set1Value(int index, int i);
   public void set1Value(int index, ConstSFInt32 i);
   public void set1Value(int index, SFInt32 i);

   public void addValue(int i);
   public void addValue(ConstSFInt32 i);
   public void addValue(SFInt32 i);

   public void insertValue(int index, int i);
   public void insertValue(int index, ConstSFInt32 i);
   public void insertValue(int index, SFInt32 i);
   // This overrides a method in Object
   public String toString();
}

public class MFNode extends MField
{
   public MFNode();
   public MFNode(int size, BaseNode node[]);
   public MFNode(BaseNode node[]);

   public void getValue(BaseNode node[]);

   public void setValue(BaseNode node[]);
   public void setValue(int size, BaseNode node[]);
   public void setValue(MFNode node);
   public void setValue(ConstMFNode node);

   public BaseNode get1Value(int index);

   public void set1Value(int index, BaseNode node);
   public void set1Value(int index, ConstSFNode node);
   public void set1Value(int index, SFNode node);

   public void addValue(BaseNode node);
   public void addValue(ConstSFNode node);
   public void addValue(SFNode node);

   public void insertValue(int index, BaseNode node);
   public void insertValue(int index, ConstSFNode node);
   public void insertValue(int index, SFNode node);

   // This overrides a method in Object
   public String toString();
}

public class MFRotation extends MField
{
   public MFRotation();
   public MFRotation(float rotations[][]);
   public MFRotation(float rotations[]);
   public MFRotation(int size, float rotations[]);

   public void getValue(float rotations[][]);
   public void getValue(float rotations[]);

   public void setValue(float rotations[][]);
   public void setValue(float rotations[]);
   public void setValue(int size, float rotations[]);
   public void setValue(MFRotation rotations);
   public void setValue(ConstMFRotation rotations);

   public void get1Value(int index, float rotations[]);
   public void get1Value(int index, SFRotation rotation);

   public void set1Value(int index, ConstSFRotation rotation);
   public void set1Value(int index, SFRotation rotation);
   public void set1Value(int index, float axisX, float axisY, float axisZ, float angle);

   public void addValue(ConstSFRotation rotation);
   public void addValue(SFRotation rotation);
   public void addValue(float axisX, float axisY, float axisZ, float angle);

   public void insertValue(int index, ConstSFRotation rotation);
   public void insertValue(int index, SFRotation rotation);
   public void insertValue(int index, float axisX, float axisY, float axisZ, float angle);

   // This overrides a method in Object
   public String toString();
}

public class MFString extends MField
{
   public MFString();
   public MFString(int size, String s[]);
   public MFString(String s[]);

   public void getValue(String s[]);

   public void setValue(String s[]);
   public void setValue(int size, String s[]);
   public void setValue(MFString s);
   public void setValue(ConstMFString s);

   public String get1Value(int index);

   public void set1Value(int index, String s);
   public void set1Value(int index, ConstSFString s);
   public void set1Value(int index, SFString s);

   public void addValue(String s);
   public void addValue(ConstSFString s);
   public void addValue(SFString s);

   public void insertValue(int index, String s);
   public void insertValue(int index, ConstSFString s);
   public void insertValue(int index, SFString s);

   // This overrides a method in Object
   public String toString();
}

public class MFTime extends MField
{
   public MFTime();
   public MFTime(int size, double times[]);
   public MFTime(double times[]);

   public void getValue(double times[]);

   public void setValue(double times[]);
   public void setValue(int size, double times[]);
   public void setValue(MFTime times);
   public void setValue(ConstMFTime times);

   public double get1Value(int index);

   public void set1Value(int index, double time);
   public void set1Value(int index, ConstSFTime time);
   public void set1Value(int index, SFTime time);

   public void addValue(double time);
   public void addValue(ConstSFTime time);
   public void addValue(SFTime time);

   public void insertValue(int index, double time);
   public void insertValue(int index, ConstSFTime time);
   public void insertValue(int index, SFTime time);

   // This overrides a method in Object
   public String toString();
}

public class MFVec2f extends MField
{
   public MFVec2f();
   public MFVec2f(float vec2s[][]);
   public MFVec2f(float vec2s[]);
   public MFVec2f(int size, float vec2s[]);

   public void getValue(float vec2s[][]);
   public void getValue(float vec2s[]);

   public void setValue(float vec2s[][]);
   public void setValue(float vec2s[]);
   public void setValue(int size, float vec2s[]);
   public void setValue(MFVec2f vecs);
   public void setValue(ConstMFVec2f vecs);

   public void get1Value(int index, float vec2s[]);
   public void get1Value(int index, SFVec2f vec);

   public void set1Value(int index, float x, float y);
   public void set1Value(int index, ConstSFVec2f vec);
   public void set1Value(int index, SFVec2f vec);

   public void addValue(float x, float y);
   public void addValue(ConstSFVec2f vec);
   public void addValue(SFVec2f vec);

   public void insertValue(int index, float x, float y);
   public void insertValue(int index, ConstSFVec2f vec);
   public void insertValue(int index, SFVec2f vec);

   // This overrides a method in Object
   public String toString();
}

public class MFVec3f extends MField
{
   public MFVec3f();
   public MFVec3f(float vec3s[][]);
   public MFVec3f(float vec3s[]);
   public MFVec3f(int size, float vec3s[]);

   public void getValue(float vec3s[][]);
   public void getValue(float vec3s[]);

   public void setValue(float vec3s[][]);
   public void setValue(float vec3s[]);
   public void setValue(int size, float vec3s[]);
   public void setValue(MFVec3f vecs);
   public void setValue(ConstMFVec3f vecs);

   public void get1Value(int index, float vec3s[]);
   public void get1Value(int index, SFVec3f vec);

   public void set1Value(int index, float x, float y, float z);
   public void set1Value(int index, ConstSFVec3f vec);
   public void set1Value(int index, SFVec3f vec);

   public void addValue(float x, float y, float z);
   public void addValue(ConstSFVec3f vec);
   public void addValue(SFVec3f vec);

   public void insertValue(int index, float x, float y, float z);
   public void insertValue(int index, ConstSFVec3f vec);
   public void insertValue(int index, SFVec3f vec);

   // This overrides a method in Object
   public String toString();
}

C.8.2.3 vrml.node Package

package vrml.node;

//
// This is the general Node class
// 
public abstract class Node extends BaseNode { 
  
  // Get an EventIn by name. Return value is write-only.
  //   Throws an InvalidEventInException if eventInName isn't a valid
  //   event in name for a node of this type.
  public final Field getEventIn(String fieldName);

  // Get an EventOut by name. Return value is read-only.
  //   Throws an InvalidEventOutException if eventOutName isn't a valid
  //   event out name for a node of this type.
  public final ConstField getEventOut(String fieldName);

  // Get an exposed field by name. 
  //   Throws an InvalidExposedFieldException if fieldName isn't a valid
  //   exposed field name for a node of this type.
  public final Field getExposedField(String fieldName);

  // This overrides a method in Object
  public String toString();
}

//
// This is the general Script class, to be subclassed by all scripts.
// Note that the provided methods allow the script author to explicitly
// throw tailored exceptions in case something goes wrong in the
// script.
//
public abstract class Script extends BaseNode { 
 
  // This method is called before any event is generated
  public void initialize();

  // Get a Field by name.
  //   Throws an InvalidFieldException if fieldName isn't a valid
  //   event in name for a node of this type.
  protected final Field getField(String fieldName);

  // Get an EventOut by name.
  //   Throws an InvalidEventOutException if eventOutName isn't a valid
  //   event out name for a node of this type.
  protected final Field getEventOut(String fieldName);

  // Get an EventIn by name.
  //   Throws an InvalidEventInException if eventInName isn't a valid
  //   event out name for a node of this type.
  protected final Field getEventIn(String fieldName);

  // processEvents() is called automatically when the script receives 
  //   some set of events. It should not be called directly except by its subclass.
  //   count indicates the number of events delivered.
  public void processEvents(int count, Event events[]);

  // processEvent() is called automatically when the script receives 
  // an event. 
  public void processEvent(Event event);

  // eventsProcessed() is called after every invocation of processEvents().
  public void eventsProcessed()

  // shutdown() is called when this Script node is deleted.
  public void shutdown();

  // This overrides a method in Object
  public String toString();
}

C.9 Example of Exception Class

public class InvalidEventInException extends IllegalArgumentException
{
   /**
    * Constructs an InvalidEventInException with no detail message.
    */
   public InvalidEventInException(){
      super();
   }
   /**
    * Constructs an InvalidEventInException with the specified detail message.
    * A detail message is a String that describes this particular exception.
    * @param s the detail message
    */
   public InvalidEventInException(String s){
      super(s);
   }
}

public class InvalidEventOutException extends IllegalArgumentException
{
   public InvalidEventOutException(){
      super();
   }
   public InvalidEventOutException(String s){
      super(s);
   }
}

public class InvalidFieldException extends IllegalArgumentException
{
   public InvalidFieldException(){
      super();
   }
   public InvalidFieldException(String s){
      super(s);
   }
}

public class InvalidExposedFieldException extends IllegalArgumentException
{
   public InvalidExposedFieldException(){
      super();
   }
   public InvalidExposedFieldException(String s){
      super(s);
   }
}

public class InvalidVRMLSyntaxException extends Exception
{
   public InvalidVRMLSyntaxException(){
      super();
   }
   public InvalidVRMLSyntaxException(String s){
      super(s);
   }
   // This overrides a method in Exception
   public String getMessage();
}

public class InvalidRouteException extends IllegalArgumentException
{
   public InvalidRouteException(){
      super();
   }
   public InvalidRouteException(String s){
      super(s);
   }
}

public class InvalidFieldChangeException extends IllegalArgumentException
{
   public InvalidFieldChangeException(){
      super();
   }
   public InvalidFieldChangeException(String s){
      super(s);
   }
}

Contact matsuda@arch.sony.co.jp(Kou1 Ma2da), sugino@ssd.sony.co.jp, or honda@arch.sony.co.jp with questions or comments.
This URL: http://vrml.sgi.com/moving-worlds/spec/part1/java.html.