public abstract class Validator
extends java.lang.Object
A processor that checks an XML document against Schema.
 A validator is a thread-unsafe and non-reentrant object.
 In other words, it is the application's responsibility to make
 sure that one Validator object is not used from
 more than one thread at any given time, and while the validate
 method is invoked, applications may not recursively call
 the validate method.
 
 Note that while the validate(javax.xml.transform.Source) and validate(javax.xml.transform.Source, javax.xml.transform.Result)
 methods take a Source instance, the Source
 instance must be a SAXSource, DOMSource, StAXSource or StreamSource.
| Modifier | Constructor and Description | 
|---|---|
| protected  | Validator()Constructor for derived classes. | 
| Modifier and Type | Method and Description | 
|---|---|
| abstract ErrorHandler | getErrorHandler()Gets the current  ErrorHandlerset to thisValidator. | 
| boolean | getFeature(java.lang.String name)Look up the value of a feature flag. | 
| java.lang.Object | getProperty(java.lang.String name)Look up the value of a property. | 
| abstract LSResourceResolver | getResourceResolver()Gets the current  LSResourceResolverset to thisValidator. | 
| abstract void | reset()Reset this  Validatorto its original configuration. | 
| abstract void | setErrorHandler(ErrorHandler errorHandler)Sets the  ErrorHandlerto receive errors encountered
 during thevalidatemethod invocation. | 
| void | setFeature(java.lang.String name,
          boolean value)Set the value of a feature flag. | 
| void | setProperty(java.lang.String name,
           java.lang.Object object)Set the value of a property. | 
| abstract void | setResourceResolver(LSResourceResolver resourceResolver)Sets the  LSResourceResolverto customize
 resource resolution while in a validation episode. | 
| void | validate(Source source)Validates the specified input. | 
| abstract void | validate(Source source,
        Result result)Validates the specified input and send the augmented validation
 result to the specified output. | 
protected Validator()
The constructor does nothing.
 Derived classes must create Validator objects that have
 null ErrorHandler and
 null LSResourceResolver.
public abstract void reset()
Reset this Validator to its original configuration.
Validator is reset to the same state as when it was created with
 Schema.newValidator().
 reset() is designed to allow the reuse of existing Validators
 thus saving resources associated with the creation of new Validators.
The reset Validator is not guaranteed to have the same LSResourceResolver or ErrorHandler
 Objects, e.g. Object.equals(Object obj).  It is guaranteed to have a functionally equal
 LSResourceResolver and ErrorHandler.
public void validate(Source source) throws SAXException, java.io.IOException
This is just a convenience method of:
validate(source,null);
SAXExceptionjava.io.IOExceptionsetErrorHandler(ErrorHandler)public abstract void validate(Source source, Result result) throws SAXException, java.io.IOException
 This method places the following restrictions on the types of
 the Source/Result accepted.
 
 
Source/Result accepted:| SAXSource | DOMSource | StAXSource | StreamSource | |
| null | OK | OK | OK | OK | 
| SAXResult | OK | Err | Err | Err | 
| DOMResult | Err | OK | Err | Err | 
| StAXResult | Err | Err | OK | Err | 
| StreamResult | Err | Err | Err | OK | 
 To validate one Source into another kind of Result, use the identity transformer
 (see TransformerFactory.newTransformer()).
 
 
 Errors found during the validation is sent to the specified
 ErrorHandler.
 
 
 If a document is valid, or if a document contains some errors
 but none of them were fatal and the ErrorHandler didn't
 throw any exception, then the method returns normally.
source - XML to be validated. Must not be null.result - The Result object that receives (possibly augmented)
      XML. This parameter can be null if the caller is not interested
      in it.
      
      Note that when a DOMResult is used,
      a validator might just pass the same DOM node from
      DOMSource to
      DOMResult
      (in which case source.getNode()==result.getNode()),
      it might copy the entire DOM tree, or it might alter the
      node given by the source.java.lang.IllegalArgumentException - If the Result type doesn't match the Source type,
      or if the specified source is not a
      SAXSource,
      DOMSource,
      StAXSource or
      StreamSource.SAXException - If the ErrorHandler throws a SAXException or
      if a fatal error is found and the ErrorHandler returns
      normally.java.io.IOException - If the validator is processing a
      SAXSource and the
      underlying XMLReader throws an
      IOException.java.lang.NullPointerException - If the source parameter is null.validate(Source)public abstract void setErrorHandler(ErrorHandler errorHandler)
ErrorHandler to receive errors encountered
 during the validate method invocation.
 
 
 Error handler can be used to customize the error handling process
 during a validation. When an ErrorHandler is set,
 errors found during the validation will be first sent
 to the ErrorHandler.
 
 
 The error handler can abort further validation immediately
 by throwing SAXException from the handler. Or for example
 it can print an error to the screen and try to continue the
 validation by returning normally from the ErrorHandler 
 
 
 If any Throwable is thrown from an ErrorHandler,
 the caller of the validate method will be thrown
 the same Throwable object.
 
 
 Validator is not allowed to
 throw SAXException without first reporting it to
 ErrorHandler.
 
 
 When the ErrorHandler is null, the implementation will
 behave as if the following ErrorHandler is set:
 
class DraconianErrorHandler implementsErrorHandler{ public void fatalError(SAXParseExceptione ) throwsSAXException{ throw e; } public void error(SAXParseExceptione ) throwsSAXException{ throw e; } public void warning(SAXParseExceptione ) throwsSAXException{ // noop } }
 When a new Validator object is created, initially
 this field is set to null.
errorHandler - A new error handler to be set. This parameter can be null.public abstract ErrorHandler getErrorHandler()
ErrorHandler set to this Validator.setErrorHandler(ErrorHandler) method, or null
      if that method has never been called since this Validator
      has created.setErrorHandler(ErrorHandler)public abstract void setResourceResolver(LSResourceResolver resourceResolver)
LSResourceResolver to customize
 resource resolution while in a validation episode.
 
 
 Validator uses a LSResourceResolver
 when it needs to locate external resources while a validation,
 although exactly what constitutes "locating external resources" is
 up to each schema language.
 
 
 When the LSResourceResolver is null, the implementation will
 behave as if the following LSResourceResolver is set:
 
class DumbLSResourceResolver implementsLSResourceResolver{ publicLSInputresolveResource( String publicId, String systemId, String baseURI) { return null; // always return null } }
 If a LSResourceResolver throws a RuntimeException
  (or instances of its derived classes),
 then the Validator will abort the parsing and  
 the caller of the validate method will receive
 the same RuntimeException. 
 
 
 When a new Validator object is created, initially
 this field is set to null.
resourceResolver - A new resource resolver to be set. This parameter can be null.public abstract LSResourceResolver getResourceResolver()
LSResourceResolver set to this Validator.setResourceResolver(LSResourceResolver) method, or null
      if that method has never been called since this Validator
      has created.setErrorHandler(ErrorHandler)public boolean getFeature(java.lang.String name)
                   throws SAXNotRecognizedException,
                          SAXNotSupportedException
The feature name is any fully-qualified URI.  It is
 possible for a Validator to recognize a feature name but
 temporarily be unable to return its value.
 Some feature values may be available only in specific
 contexts, such as before, during, or after a validation.
 
Implementors are free (and encouraged) to invent their own features, using names built on their own URIs.
name - The feature name, which is a non-null fully-qualified URI.SAXNotRecognizedException - If the feature
            value can't be assigned or retrieved.SAXNotSupportedException - When the
            Validator recognizes the feature name but 
            cannot determine its value at this time.java.lang.NullPointerException - When the name parameter is null.setFeature(String, boolean)public void setFeature(java.lang.String name,
              boolean value)
                throws SAXNotRecognizedException,
                       SAXNotSupportedException
 Feature can be used to control the way a Validator
 parses schemas, although Validators are not required
 to recognize any specific property names.
The feature name is any fully-qualified URI.  It is
 possible for a Validator to expose a feature value but
 to be unable to change the current value.
 Some feature values may be immutable or mutable only 
 in specific contexts, such as before, during, or after 
 a validation.
name - The feature name, which is a non-null fully-qualified URI.value - The requested value of the feature (true or false).SAXNotRecognizedException - If the feature
            value can't be assigned or retrieved.SAXNotSupportedException - When the
            Validator recognizes the feature name but 
            cannot set the requested value.java.lang.NullPointerException - When the name parameter is null.getFeature(String)public void setProperty(java.lang.String name,
               java.lang.Object object)
                 throws SAXNotRecognizedException,
                        SAXNotSupportedException
The property name is any fully-qualified URI.  It is
 possible for a Validator to recognize a property name but
 to be unable to change the current value.
 Some property values may be immutable or mutable only 
 in specific contexts, such as before, during, or after 
 a validation.
Validators are not required to recognize setting
 any specific property names.
name - The property name, which is a non-null fully-qualified URI.object - The requested value for the property.SAXNotRecognizedException - If the property
            value can't be assigned or retrieved.SAXNotSupportedException - When the
            Validator recognizes the property name but 
            cannot set the requested value.java.lang.NullPointerException - When the name parameter is null.public java.lang.Object getProperty(java.lang.String name)
                             throws SAXNotRecognizedException,
                                    SAXNotSupportedException
The property name is any fully-qualified URI.  It is
 possible for a Validator to recognize a property name but
 temporarily be unable to return its value.
 Some property values may be available only in specific
 contexts, such as before, during, or after a validation.
Validators are not required to recognize any specific
 property names.
Implementors are free (and encouraged) to invent their own properties, using names built on their own URIs.
name - The property name, which is a non-null fully-qualified URI.SAXNotRecognizedException - If the property
            value can't be assigned or retrieved.SAXNotSupportedException - When the
            XMLReader recognizes the property name but 
            cannot determine its value at this time.java.lang.NullPointerException - When the name parameter is null.setProperty(String, Object)Copyright © 1999-2022 The Apache Software Foundation. All Rights Reserved.