Implements pluggable Datatypes.
* - *This class is duplicated for each JAXP subpackage so keep it in - * sync. It is package private for secure class loading.
+ *This class is duplicated for each JAXP subpackage so keep it in sync. It + * is package private for secure class loading.
* * @author Santiago.PericasGeertsen@sun.com * @author Huizhe.Wang@oracle.com @@ -47,21 +47,18 @@ * Internal debug flag. */ private static boolean debug = false; - /** * Cache for properties in java.home/lib/jaxp.properties */ static Properties cacheProps = new Properties(); - /** - * Flag indicating if properties from java.home/lib/jaxp.properties - * have been cached. + * Flag indicating if properties from java.home/lib/jaxp.properties have + * been cached. */ static volatile boolean firstTime = true; - /** - * Security support class use to check access control before - * getting certain system resources. + * Security support class use to check access control before getting certain + * system resources. */ static SecuritySupport ss = new SecuritySupport(); @@ -73,8 +70,7 @@ String val = ss.getSystemProperty("jaxp.debug"); // Allow simply setting the prop to turn on debug debug = val != null && !"false".equals(val); - } - catch (SecurityException se) { + } catch (SecurityException se) { debug = false; } } @@ -90,15 +86,14 @@ * and fall back is enabled, the current (i.e. bootstrap) class loader is * tried. * - * If the class loader supplied isnull, first try using the
- * context class loader followed by the current (i.e. bootstrap) class
- * loader.
+ * If the class loader supplied is
+ * null, first try using the context class loader followed by
+ * the current (i.e. bootstrap) class loader.
*
* Use bootstrap classLoader if cl = null and useBSClsLoader is true
*/
static private Class getProviderClass(String className, ClassLoader cl,
- boolean doFallback, boolean useBSClsLoader) throws ClassNotFoundException
- {
+ boolean doFallback, boolean useBSClsLoader) throws ClassNotFoundException {
try {
if (cl == null) {
if (useBSClsLoader) {
@@ -107,22 +102,18 @@
cl = ss.getContextClassLoader();
if (cl == null) {
throw new ClassNotFoundException();
- }
- else {
+ } else {
return cl.loadClass(className);
}
}
- }
- else {
+ } else {
return cl.loadClass(className);
}
- }
- catch (ClassNotFoundException e1) {
+ } catch (ClassNotFoundException e1) {
if (doFallback) {
// Use current class loader - should always be bootstrap CL
return Class.forName(className, true, FactoryFinder.class.getClassLoader());
- }
- else {
+ } else {
throw e1;
}
}
@@ -132,18 +123,18 @@
* Create an instance of a class. Delegates to method
* getProviderClass() in order to load the class.
*
- * @param className Name of the concrete class corresponding to the
- * service provider
+ * @param className Name of the concrete class corresponding to the service
+ * provider
*
- * @param cl ClassLoader used to load the factory class. If null
- * current Thread's context classLoader is used to load the factory class.
+ * @param cl ClassLoader used to load the factory class.
+ * If null current Thread's context classLoader is
+ * used to load the factory class.
*
- * @param doFallback True if the current ClassLoader should be tried as
- * a fallback if the class is not found using cl
+ * @param doFallback True if the current ClassLoader should be tried as a
+ * fallback if the class is not found using cl
*/
static Object newInstance(String className, ClassLoader cl, boolean doFallback)
- throws ConfigurationError
- {
+ throws FactoryConfigurationError {
return newInstance(className, cl, doFallback, false);
}
@@ -151,56 +142,54 @@
* Create an instance of a class. Delegates to method
* getProviderClass() in order to load the class.
*
- * @param className Name of the concrete class corresponding to the
- * service provider
- *
- * @param cl ClassLoader used to load the factory class. If null
- * current Thread's context classLoader is used to load the factory class.
+ * @param className Name of the concrete class corresponding to the service
+ * provider
*
- * @param doFallback True if the current ClassLoader should be tried as
- * a fallback if the class is not found using cl
- *
- * @param useBSClsLoader True if cl=null actually meant bootstrap classLoader. This parameter
- * is needed since DocumentBuilderFactory/SAXParserFactory defined null as context classLoader.
+ * @param cl ClassLoader used to load the factory class.
+ * If null current Thread's context classLoader is
+ * used to load the factory class.
+ *
+ * @param doFallback True if the current ClassLoader should be tried as a
+ * fallback if the class is not found using cl
+ *
+ * @param useBSClsLoader True if cl=null actually meant bootstrap
+ * classLoader. This parameter is needed since
+ * DocumentBuilderFactory/SAXParserFactory defined null as context
+ * classLoader.
*/
static Object newInstance(String className, ClassLoader cl, boolean doFallback, boolean useBSClsLoader)
- throws ConfigurationError
- {
+ throws FactoryConfigurationError {
try {
Class providerClass = getProviderClass(className, cl, doFallback, useBSClsLoader);
Object instance = providerClass.newInstance();
if (debug) { // Extra check to avoid computing cl strings
- dPrint("created new instance of " + providerClass +
- " using ClassLoader: " + cl);
+ dPrint("created new instance of " + providerClass
+ + " using ClassLoader: " + cl);
}
return instance;
- }
- catch (ClassNotFoundException x) {
- throw new ConfigurationError(
- "Provider " + className + " not found", x);
- }
- catch (Exception x) {
- throw new ConfigurationError(
- "Provider " + className + " could not be instantiated: " + x,
- x);
+ } catch (ClassNotFoundException x) {
+ throw new FactoryConfigurationError(x,
+ "Provider " + className + " not found");
+ } catch (Exception x) {
+ throw new FactoryConfigurationError(x,
+ "Provider " + className + " could not be instantiated: " + x);
}
}
/**
- * Finds the implementation Class object in the specified order. Main
- * entry point.
+ * Finds the implementation Class object in the specified order. Main entry
+ * point.
+ *
* @return Class object of factory, never null
*
- * @param factoryId Name of the factory to find, same as
- * a property name
- * @param fallbackClassName Implementation class name, if nothing else
- * is found. Use null to mean no fallback.
+ * @param factoryId Name of the factory to find, same as a property name
+ * @param fallbackClassName Implementation class name, if nothing else is
+ * found. Use null to mean no fallback.
*
* Package private so this code can be shared.
*/
- static Object find(String factoryId, String fallbackClassName)
- throws ConfigurationError
- {
+ static Object find(Class factoryClass, String factoryId, String fallbackClassName)
+ throws FactoryConfigurationError {
dPrint("find factoryId =" + factoryId);
// Use the system property first
@@ -210,9 +199,10 @@
dPrint("found system property, value=" + systemProp);
return newInstance(systemProp, null, true);
}
- }
- catch (SecurityException se) {
- if (debug) se.printStackTrace();
+ } catch (SecurityException se) {
+ if (debug) {
+ se.printStackTrace();
+ }
}
// try to read from $java.home/lib/jaxp.properties
@@ -221,12 +211,12 @@
if (firstTime) {
synchronized (cacheProps) {
if (firstTime) {
- String configFile = ss.getSystemProperty("java.home") + File.separator +
- "lib" + File.separator + "jaxp.properties";
+ String configFile = ss.getSystemProperty("java.home") + File.separator
+ + "lib" + File.separator + "jaxp.properties";
File f = new File(configFile);
firstTime = false;
if (ss.doesFileExist(f)) {
- dPrint("Read properties file "+f);
+ dPrint("Read properties file " + f);
cacheProps.load(ss.getFileInputStream(f));
}
}
@@ -238,19 +228,25 @@
dPrint("found in $java.home/jaxp.properties, value=" + factoryClassName);
return newInstance(factoryClassName, null, true);
}
- }
- catch (Exception ex) {
- if (debug) ex.printStackTrace();
+ } catch (Exception ex) {
+ if (debug) {
+ ex.printStackTrace();
+ }
}
- // Try Jar Service Provider Mechanism
- Object provider = findJarServiceProvider(factoryId);
- if (provider != null) {
- return provider;
+ // Try service-provider loading facilities
+ try {
+ Object provider = findServiceProvider(factoryClass, fallbackClassName);
+ if (provider != null) {
+ return provider;
+ }
+ } catch (FactoryConfigurationError e) {
+ throw e;
}
+
+ // Last, check if fallback is requested
if (fallbackClassName == null) {
- throw new ConfigurationError(
- "Provider for " + factoryId + " cannot be found", null);
+ throw new FactoryConfigurationError("Provider for " + factoryId + " cannot be found");
}
dPrint("loaded from fallback value: " + fallbackClassName);
@@ -258,99 +254,31 @@
}
/*
- * Try to find provider using Jar Service Provider Mechanism
+ * Try to find a provider using Service Loader
*
* @return instance of provider class if found or null
*/
- private static Object findJarServiceProvider(String factoryId)
- throws ConfigurationError
- {
- String serviceId = "META-INF/services/" + factoryId;
- InputStream is = null;
-
- // First try the Context ClassLoader
- ClassLoader cl = ss.getContextClassLoader();
- boolean useBSClsLoader = false;
- if (cl != null) {
- is = ss.getResourceAsStream(cl, serviceId);
-
- // If no provider found then try the current ClassLoader
- if (is == null) {
- cl = FactoryFinder.class.getClassLoader();
- is = ss.getResourceAsStream(cl, serviceId);
- useBSClsLoader = true;
- }
- } else {
- // No Context ClassLoader, try the current ClassLoader
- cl = FactoryFinder.class.getClassLoader();
- is = ss.getResourceAsStream(cl, serviceId);
- useBSClsLoader = true;
- }
-
- if (is == null) {
- // No provider found
- return null;
- }
-
- if (debug) { // Extra check to avoid computing cl strings
- dPrint("found jar resource=" + serviceId + " using ClassLoader: " + cl);
- }
-
- BufferedReader rd;
- try {
- rd = new BufferedReader(new InputStreamReader(is, "UTF-8"));
- }
- catch (java.io.UnsupportedEncodingException e) {
- rd = new BufferedReader(new InputStreamReader(is));
- }
-
- String factoryClassName = null;
+ private static Object findServiceProvider(final Class factoryClass, final String fallbackClassName)
+ throws FactoryConfigurationError {
try {
- // XXX Does not handle all possible input as specified by the
- // Jar Service Provider specification
- factoryClassName = rd.readLine();
- rd.close();
- } catch (IOException x) {
- // No provider found
- return null;
- }
-
- if (factoryClassName != null && !"".equals(factoryClassName)) {
- dPrint("found in resource, value=" + factoryClassName);
-
- // Note: here we do not want to fall back to the current
- // ClassLoader because we want to avoid the case where the
- // resource file was found using one ClassLoader and the
- // provider class was instantiated using a different one.
- return newInstance(factoryClassName, cl, false, useBSClsLoader);
- }
-
- // No provider found
- return null;
- }
-
- static class ConfigurationError extends Error {
- private Exception exception;
-
- /**
- * Construct a new instance with the specified detail string and
- * exception.
- */
- ConfigurationError(String msg, Exception x) {
- super(msg);
- this.exception = x;
- }
-
- Exception getException() {
- return exception;
- }
- /**
- * use the exception chaining mechanism of JDK1.4
- */
- @Override
- public Throwable getCause() {
- return exception;
+ return AccessController.doPrivileged(new PrivilegedAction() {
+ public Object run() {
+ Object defaultProvider = null;
+ for (Object factory : ServiceLoader.load(factoryClass)) {
+ if (factory.getClass().getName().equals(fallbackClassName)) {
+ defaultProvider = factory;
+ } else {
+ return factory;
+ }
+ }
+ if (defaultProvider != null) {
+ return defaultProvider;
+ }
+ return null;
+ }
+ });
+ } catch (ServiceConfigurationError e) {
+ throw new FactoryConfigurationError((Exception) e.getCause(), e.getMessage());
}
}
-
}