src/javax/xml/parsers/FactoryFinder.java
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@@ -23,47 +23,44 @@
* questions.
*/
package javax.xml.parsers;
-import java.io.BufferedReader;
import java.io.File;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.InputStreamReader;
+import java.security.AccessController;
+import java.security.PrivilegedAction;
import java.util.Properties;
+import java.util.ServiceConfigurationError;
+import java.util.ServiceLoader;
/**
* <p>Implements pluggable Datatypes.</p>
*
- * <p>This class is duplicated for each JAXP subpackage so keep it in
- * sync. It is package private for secure class loading.</p>
+ * <p>This class is duplicated for each JAXP subpackage so keep it in sync. It
+ * is package private for secure class loading.</p>
*
* @author Santiago.PericasGeertsen@sun.com
* @author Huizhe.Wang@oracle.com
*/
class FactoryFinder {
/**
* 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();
// Define system property "jaxp.debug" to get output
static {
@@ -71,12 +68,11 @@
// SecurityException out of this code.
try {
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;
}
}
private static void dPrint(String msg) {
@@ -88,147 +84,141 @@
/**
* Attempt to load a class using the class loader supplied. If that fails
* and fall back is enabled, the current (i.e. bootstrap) class loader is
* tried.
*
- * If the class loader supplied is <code>null</code>, first try using the
- * context class loader followed by the current (i.e. bootstrap) class
- * loader.
+ * If the class loader supplied is
+ * <code>null</code>, 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) {
return Class.forName(className, true, FactoryFinder.class.getClassLoader());
} else {
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;
}
}
}
/**
* Create an instance of a class. Delegates to method
* <code>getProviderClass()</code> 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 <code>ClassLoader</code> used to load the factory class. If <code>null</code>
- * current <code>Thread</code>'s context classLoader is used to load the factory class.
+ * @param cl <code>ClassLoader</code> used to load the factory class.
+ * If <code>null</code> current <code>Thread</code>'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);
}
/**
* Create an instance of a class. Delegates to method
* <code>getProviderClass()</code> in order to load the class.
*
- * @param className Name of the concrete class corresponding to the
- * service provider
- *
- * @param cl <code>ClassLoader</code> used to load the factory class. If <code>null</code>
- * current <code>Thread</code>'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 className Name of the concrete class corresponding to the service
+ * provider
*
- * @param useBSClsLoader True if cl=null actually meant bootstrap classLoader. This parameter
- * is needed since DocumentBuilderFactory/SAXParserFactory defined null as context classLoader.
+ * @param cl <code>ClassLoader</code> used to load the factory class.
+ * If <code>null</code> current <code>Thread</code>'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
try {
String systemProp = ss.getSystemProperty(factoryId);
if (systemProp != null) {
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
try {
String factoryClassName = null;
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));
}
}
}
}
@@ -236,121 +226,59 @@
if (factoryClassName != null) {
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);
+ // 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);
return newInstance(fallbackClassName, null, true);
}
/*
- * 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;
+ private static Object findServiceProvider(final Class factoryClass, final String fallbackClassName)
+ throws FactoryConfigurationError {
try {
- rd = new BufferedReader(new InputStreamReader(is, "UTF-8"));
- }
- catch (java.io.UnsupportedEncodingException e) {
- rd = new BufferedReader(new InputStreamReader(is));
+ 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;
}
-
- String factoryClassName = null;
- 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);
+ if (defaultProvider != null) {
+ return defaultProvider;
}
-
- // 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;
+ });
+ } catch (ServiceConfigurationError e) {
+ throw new FactoryConfigurationError((Exception) e.getCause(), e.getMessage());
}
}
-
}