Class State

java.lang.Object
com.sun.msv.reader.State
All Implemented Interfaces:
ContentHandler
Direct Known Subclasses:
IgnoreState, NamespaceState, SimpleState

public abstract class State extends Object implements ContentHandler
base interface of 'parsing state'. parsing of XML representation of a grammar is done by using various states.

Each State-derived class is responsible for a particular type of declaration of the grammar. For example, SequenceState is responsible for parsing <sequence> element of RELAX module.

State objects interact each other. There are two ways of interaction.

  • from parent to child
  • from child to parent
The first type of communication occurs only when a child state object is created. The last type of communication occurs usually (but not limited to) when a child state sees its end tag.

In this level of inheritance, contract is somewhat abstract.

  1. When a State object is created, its init method is called and various information is set. Particularly, start tag information (if any) and the parent state is set. This process should only be initiated by GrammarReader.
  2. After that, startSelf method is called. Usually, this is the place to do something useful.
  3. State object is registered as a ContentHandler, and therefore will receive SAX events from now on.
  4. Derived classes are expected to do something useful by receiving SAX events.
  5. When a State object finishes its own part, it should call GrammarReader.popState method. It will remove the current State object and registers the parent state as a ContentHandler again.
Of course some derived classes introduce more restricted contract. See SimpleState.

this class also provides:

  • access to the parent state
  • default implementations for all ContentHandler callbacks except startElement and endElement
Author:
Kohsuke KAWAGUCHI
  • Field Details

    • parentState

      protected State parentState
      parent state of this state. In other words, the parent state is a state who is responsible for the parent element of the current element. For states responsible for the document element, the parent state is a state who is responsible for the entire document. For states responsible for the entire document, the parent state is always null.
    • reader

      public GrammarReader reader
      reader object who is the owner of this object. This information is avaiable after init method is called.
    • startTag

      protected StartTagInfo startTag
      information of the start tag. This information is avaiable after init method is called.
    • location

      protected Locator location
      Location of the start tag. This information is avaiable after init method is called.
    • baseURI

      protected String baseURI
      base URI for this state. This information is avaiable after init method is called.
  • Constructor Details

    • State

      public State()
  • Method Details