org.codehaus.stax2.validation.XMLValidationSchemaFactory Maven / Gradle / Ivy
package org.codehaus.stax2.validation;
import java.io.*;
import java.net.URL;
import java.util.*;
import javax.xml.stream.FactoryConfigurationError;
import javax.xml.stream.XMLStreamException;
/**
* Defines an abstract factory for constructing {@link XMLValidationSchema}
* instances. This abstract base class has methods for instantiating the
* actual implementation (similar to the way
* {@link javax.xml.stream.XMLInputFactory} works, and defines the API to
* use for configuring these instances, as well as factory methods concrete
* classes implement for actually creating {@link XMLValidationSchema}
* instances.
*
* Note: this class is part of the second major revision of StAX 2 API
* (StAX2, v2), and is optional for StAX2 implementations to support.
*
* @see javax.xml.stream.XMLInputFactory
* @see org.codehaus.stax2.validation.XMLValidationSchema
* @see org.codehaus.stax2.XMLInputFactory2
*/
public abstract class XMLValidationSchemaFactory
{
// // // Internal ids matching SCHEMA_ID_ constants from XMLValidationSchema
public final static String INTERNAL_ID_SCHEMA_DTD = "dtd";
public final static String INTERNAL_ID_SCHEMA_RELAXNG = "relaxng";
public final static String INTERNAL_ID_SCHEMA_W3C = "w3c";
public final static String INTERNAL_ID_SCHEMA_TREX = "trex";
final static HashMap sSchemaIds = new HashMap();
static {
sSchemaIds.put(XMLValidationSchema.SCHEMA_ID_DTD, INTERNAL_ID_SCHEMA_DTD);
sSchemaIds.put(XMLValidationSchema.SCHEMA_ID_RELAXNG, INTERNAL_ID_SCHEMA_RELAXNG);
sSchemaIds.put(XMLValidationSchema.SCHEMA_ID_W3C_SCHEMA, INTERNAL_ID_SCHEMA_W3C);
sSchemaIds.put(XMLValidationSchema.SCHEMA_ID_TREX, INTERNAL_ID_SCHEMA_TREX);
}
// // // Properties for locating implementations
/**
* Name of resource file that contains JAXP properties.
*/
final static String JAXP_PROP_FILENAME = "jaxp.properties";
/**
* Defines the system property that can be set to explicitly specify
* which implementation to use (in case there are multiple StAX2
* implementations; or the one used does not specify other mechanisms
* for the loader to find the implementation class).
*/
public final static String SYSTEM_PROPERTY_FOR_IMPL = "org.codehaus.stax2.validation.XMLValidationSchemaFactory.";
/**
* Path to resource that should contain implementation class definition.
*/
public final static String SERVICE_DEFINITION_PATH = "META-INF/services/" + SYSTEM_PROPERTY_FOR_IMPL;
// // // Names of standard configuration properties
/**
* Property that determines whether schemas constructed are namespace-aware,
* in cases where schema supports both namespace-aware and non-namespace
* aware modes. In general this only applies to DTDs, since namespace
* support for DTDs is both optional, and not well specified.
*
* Default value is TRUE. For schema types for which only one value
* (usually TRUE) is allowed, this property will be ignored.
*/
public static final String P_IS_NAMESPACE_AWARE = "org.codehaus2.stax2.validation.isNamespaceAware";
/**
* Property that determines whether schema instances created by this
* factory instance can be cached by the factory; if false, no caching
* is allowed to be doe; if true, factory can do caching if it wants to.
* The exact rules used to determine unique id of schema instances is
* factory dependant; it is expected that the implementations use
* implementation based on unified system ids (serialized URLs or such).
*/
public static final String P_ENABLE_CACHING = "org.codehaus2.stax2.validation.enableCaching";
/**
* Schema type this factory instance supports.
*/
protected final String mSchemaType;
/**
* @param st Schema type this factory supports; one of
* SCHEMA_ID_xxx constants.
*/
protected XMLValidationSchemaFactory(String st)
{
mSchemaType = st;
}
/*
////////////////////////////////////////////////////////
// Factory methods
////////////////////////////////////////////////////////
*/
// // // First creating the factory instances:
/**
* Creates a new XMLValidationFactory instance, using the default
* instance configuration mechanism.
*/
public static XMLValidationSchemaFactory newInstance(String schemaType)
throws FactoryConfigurationError
{
return newInstance(schemaType,
Thread.currentThread().getContextClassLoader());
}
public static XMLValidationSchemaFactory newInstance(String schemaType, ClassLoader classLoader)
throws FactoryConfigurationError
{
/* First, let's check and map schema type to the shorter internal
* id:
*/
String internalId = (String) sSchemaIds.get(schemaType);
if (internalId == null) {
throw new FactoryConfigurationError("Unrecognized schema type (id '"+schemaType+"')");
}
String propertyId = SYSTEM_PROPERTY_FOR_IMPL + internalId;
SecurityException secEx = null;
/* First, let's see if there's a system property (overrides other
* settings)
*/
try {
String clsName = System.getProperty(propertyId);
if (clsName != null && clsName.length() > 0) {
return createNewInstance(classLoader, clsName);
}
} catch (SecurityException se) {
// May happen on sandbox envs, like applets?
secEx = se;
}
/* try to read from $java.home/lib/xml.properties (simulating
* the way XMLInputFactory does this... not sure if this should
* be done, as this is not [yet?] really jaxp specified)
*/
try {
String home = System.getProperty("java.home");
File f = new File(home);
// Let's not hard-code separators...
f = new File(f, "lib");
f = new File(f, JAXP_PROP_FILENAME);
if (f.exists()) {
try {
Properties props = new Properties();
props.load(new FileInputStream(f));
String clsName = props.getProperty(propertyId);
if (clsName != null && clsName.length() > 0) {
return createNewInstance(classLoader, clsName);
}
} catch (IOException ioe) {
// can also happen quite easily...
}
}
} catch (SecurityException se) {
// Fine, as above
secEx = se;
}
/* Ok, no match; how about a service def from the impl jar?
*/
// try to find services in CLASSPATH
String path = SERVICE_DEFINITION_PATH + internalId;
try {
Enumeration en;
if (classLoader == null) {
en = ClassLoader.getSystemResources(path);
} else {
en = classLoader.getResources(path);
}
if (en != null) {
while (en.hasMoreElements()) {
URL url = (URL) en.nextElement();
InputStream is = url.openStream();
BufferedReader rd =
new BufferedReader(new InputStreamReader(is, "ISO-8859-1"));
String clsName = null;
String line;
try {
while ((line = rd.readLine()) != null) {
line = line.trim();
if (line.length() > 0 && line.charAt(0) != '#') {
clsName = line;
break;
}
}
} finally {
rd.close();
}
if (clsName != null && clsName.length() > 0) {
return createNewInstance(classLoader, clsName);
}
}
}
} catch (SecurityException se) {
secEx = se;
} catch (IOException ex) {
/* Let's assume these are mostly ok, too (missing jar ie.)
*/
}
String msg = "No XMLValidationSchemaFactory implementation class specified or accessible (via system property '"
+propertyId+"', or service definition under '"+path+"')";
if (secEx != null) {
throw new FactoryConfigurationError(msg + " (possibly caused by: "+secEx+")", secEx);
}
throw new FactoryConfigurationError(msg);
}
// // // And then actual per-instance factory methods
public XMLValidationSchema createSchema(InputStream in)
throws XMLStreamException
{
return createSchema(in, null);
}
public XMLValidationSchema createSchema(InputStream in, String encoding)
throws XMLStreamException
{
return createSchema(in, encoding, null, null);
}
public abstract XMLValidationSchema createSchema(InputStream in, String encoding,
String publicId, String systemId)
throws XMLStreamException;
public XMLValidationSchema createSchema(Reader r)
throws XMLStreamException
{
return createSchema(r, null, null);
}
public abstract XMLValidationSchema createSchema(Reader r, String publicId,
String systemId)
throws XMLStreamException;
public abstract XMLValidationSchema createSchema(URL url)
throws XMLStreamException;
public abstract XMLValidationSchema createSchema(File f)
throws XMLStreamException;
/*
////////////////////////////////////////////////////////
// Configuration
////////////////////////////////////////////////////////
*/
public abstract boolean isPropertySupported(String propName);
/**
* @param propName Name of property to set
* @param value Value to set property to
*
* @return True if setting succeeded; false if property was recognized
* but could not be changed to specified value, or if it was not
* recognized but the implementation did not throw an exception.
*/
public abstract boolean setProperty(String propName, Object value);
public abstract Object getProperty(String propName);
/**
* @return Name of schema type (one of SCHEMA_ID_xxx
* constants) that this factory supports.
*/
public final String getSchemaType() { return mSchemaType; }
/*
///////////////////////////////////////////////////////
// Internal methods
///////////////////////////////////////////////////////
*/
private static XMLValidationSchemaFactory createNewInstance(ClassLoader cloader, String clsName)
throws FactoryConfigurationError
{
try {
Class factoryClass;
if (cloader == null) {
factoryClass = Class.forName(clsName);
} else {
factoryClass = cloader.loadClass(clsName);
}
return (XMLValidationSchemaFactory) factoryClass.newInstance();
} catch (ClassNotFoundException x) {
throw new FactoryConfigurationError
("XMLValidationSchemaFactory implementation '"+clsName+"' not found (missing jar in classpath?)", x);
} catch (Exception x) {
throw new FactoryConfigurationError
("XMLValidationSchemaFactory implementation '"+clsName+"' could not be instantiated: "+x, x);
}
}
}