src/com/sun/org/apache/xalan/internal/utils/ObjectFactory.java
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@@ -21,30 +21,15 @@
* $Id: ObjectFactory.java,v 1.2.4.1 2005/09/15 02:39:54 jeffsuttor Exp $
*/
package com.sun.org.apache.xalan.internal.utils;
-import java.io.InputStream;
-import java.io.IOException;
-import java.io.File;
-import java.io.FileInputStream;
-
-import java.util.Properties;
-import java.io.BufferedReader;
-import java.io.InputStreamReader;
-
/**
* This class is duplicated for each JAXP subpackage so keep it in sync.
* It is package private and therefore is not exposed as part of the JAXP
* API.
* <p>
- * This code is designed to implement the JAXP 1.1 spec pluggability
- * feature and is designed to run on JDK version 1.1 and
- * later, and to compile on JDK 1.2 and onward.
- * The code also runs both as part of an unbundled jar file and
- * when bundled as part of the JDK.
- * <p>
* This class was moved from the <code>javax.xml.parsers.ObjectFactory</code>
* class and modified to be used as a general utility for creating objects
* dynamically.
*
* @version $Id: ObjectFactory.java,v 1.11 2010-11-01 04:34:25 joehw Exp $
@@ -55,333 +40,13 @@
// Constants
//
private static final String XALAN_INTERNAL = "com.sun.org.apache.xalan.internal";
private static final String XERCES_INTERNAL = "com.sun.org.apache.xerces.internal";
- // name of default properties file to look for in JDK's jre/lib directory
- private static final String DEFAULT_PROPERTIES_FILENAME =
- "xalan.properties";
-
- private static final String SERVICES_PATH = "META-INF/services/";
-
/** Set to true for debugging */
private static final boolean DEBUG = false;
- /** cache the contents of the xalan.properties file.
- * Until an attempt has been made to read this file, this will
- * be null; if the file does not exist or we encounter some other error
- * during the read, this will be empty.
- */
- private static Properties fXalanProperties = null;
-
- /***
- * Cache the time stamp of the xalan.properties file so
- * that we know if it's been modified and can invalidate
- * the cache when necessary.
- */
- private static long fLastModified = -1;
-
- //
- // Public static methods
- //
-
- /**
- * Finds the implementation Class object in the specified order. The
- * specified order is the following:
- * <ol>
- * <li>query the system property using <code>System.getProperty</code>
- * <li>read <code>META-INF/services/<i>factoryId</i></code> file
- * <li>use fallback classname
- * </ol>
- *
- * @return instance 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.
- *
- * @exception ObjectFactory.ConfigurationError
- */
- public static Object createObject(String factoryId, String fallbackClassName)
- throws ConfigurationError {
- return createObject(factoryId, null, fallbackClassName);
- } // createObject(String,String):Object
-
- /**
- * Finds the implementation Class object in the specified order. The
- * specified order is the following:
- * <ol>
- * <li>query the system property using <code>System.getProperty</code>
- * <li>read <code>$java.home/lib/<i>propertiesFilename</i></code> file
- * <li>read <code>META-INF/services/<i>factoryId</i></code> file
- * <li>use fallback classname
- * </ol>
- *
- * @return instance of factory, never null
- *
- * @param factoryId Name of the factory to find, same as
- * a property name
- * @param propertiesFilename The filename in the $java.home/lib directory
- * of the properties file. If none specified,
- * ${java.home}/lib/xalan.properties will be used.
- * @param fallbackClassName Implementation class name, if nothing else
- * is found. Use null to mean no fallback.
- *
- * @exception ObjectFactory.ConfigurationError
- */
- static Object createObject(String factoryId,
- String propertiesFilename,
- String fallbackClassName)
- throws ConfigurationError
- {
- Class factoryClass = lookUpFactoryClass(factoryId,
- propertiesFilename,
- fallbackClassName);
-
- if (factoryClass == null) {
- throw new ConfigurationError(
- "Provider for " + factoryId + " cannot be found", null);
- }
-
- try{
- Object instance = factoryClass.newInstance();
- if (DEBUG) debugPrintln("created new instance of factory " + factoryId);
- return instance;
- } catch (Exception x) {
- throw new ConfigurationError(
- "Provider for factory " + factoryId
- + " could not be instantiated: " + x, x);
- }
- } // createObject(String,String,String):Object
-
- /**
- * Finds the implementation Class object in the specified order. The
- * specified order is the following:
- * <ol>
- * <li>query the system property using <code>System.getProperty</code>
- * <li>read <code>$java.home/lib/<i>propertiesFilename</i></code> file
- * <li>read <code>META-INF/services/<i>factoryId</i></code> file
- * <li>use fallback classname
- * </ol>
- *
- * @return Class object of factory, never null
- *
- * @param factoryId Name of the factory to find, same as
- * a property name
- * @param propertiesFilename The filename in the $java.home/lib directory
- * of the properties file. If none specified,
- * ${java.home}/lib/xalan.properties will be used.
- * @param fallbackClassName Implementation class name, if nothing else
- * is found. Use null to mean no fallback.
- *
- * @exception ObjectFactory.ConfigurationError
- */
- public static Class lookUpFactoryClass(String factoryId)
- throws ConfigurationError
- {
- return lookUpFactoryClass(factoryId, null, null);
- } // lookUpFactoryClass(String):Class
-
- /**
- * Finds the implementation Class object in the specified order. The
- * specified order is the following:
- * <ol>
- * <li>query the system property using <code>System.getProperty</code>
- * <li>read <code>$java.home/lib/<i>propertiesFilename</i></code> file
- * <li>read <code>META-INF/services/<i>factoryId</i></code> file
- * <li>use fallback classname
- * </ol>
- *
- * @return Class object that provides factory service, never null
- *
- * @param factoryId Name of the factory to find, same as
- * a property name
- * @param propertiesFilename The filename in the $java.home/lib directory
- * of the properties file. If none specified,
- * ${java.home}/lib/xalan.properties will be used.
- * @param fallbackClassName Implementation class name, if nothing else
- * is found. Use null to mean no fallback.
- *
- * @exception ObjectFactory.ConfigurationError
- */
- public static Class lookUpFactoryClass(String factoryId,
- String propertiesFilename,
- String fallbackClassName)
- throws ConfigurationError
- {
- String factoryClassName = lookUpFactoryClassName(factoryId,
- propertiesFilename,
- fallbackClassName);
- ClassLoader cl = findClassLoader();
-
- if (factoryClassName == null) {
- factoryClassName = fallbackClassName;
- }
-
- // assert(className != null);
- try{
- Class providerClass = findProviderClass(factoryClassName,
- cl,
- true);
- if (DEBUG) debugPrintln("created new instance of " + providerClass +
- " using ClassLoader: " + cl);
- return providerClass;
- } catch (ClassNotFoundException x) {
- throw new ConfigurationError(
- "Provider " + factoryClassName + " not found", x);
- } catch (Exception x) {
- throw new ConfigurationError(
- "Provider "+factoryClassName+" could not be instantiated: "+x,
- x);
- }
- } // lookUpFactoryClass(String,String,String):Class
-
- /**
- * Finds the name of the required implementation class in the specified
- * order. The specified order is the following:
- * <ol>
- * <li>query the system property using <code>System.getProperty</code>
- * <li>read <code>$java.home/lib/<i>propertiesFilename</i></code> file
- * <li>read <code>META-INF/services/<i>factoryId</i></code> file
- * <li>use fallback classname
- * </ol>
- *
- * @return name of class that provides factory service, never null
- *
- * @param factoryId Name of the factory to find, same as
- * a property name
- * @param propertiesFilename The filename in the $java.home/lib directory
- * of the properties file. If none specified,
- * ${java.home}/lib/xalan.properties will be used.
- * @param fallbackClassName Implementation class name, if nothing else
- * is found. Use null to mean no fallback.
- *
- * @exception ObjectFactory.ConfigurationError
- */
- static String lookUpFactoryClassName(String factoryId,
- String propertiesFilename,
- String fallbackClassName)
- {
- // Use the system property first
- try {
- String systemProp = SecuritySupport.getSystemProperty(factoryId);
- if (systemProp != null) {
- if (DEBUG) debugPrintln("found system property, value=" + systemProp);
- return systemProp;
- }
- } catch (SecurityException se) {
- // Ignore and continue w/ next location
- }
-
- // Try to read from propertiesFilename, or
- // $java.home/lib/xalan.properties
- String factoryClassName = null;
- // no properties file name specified; use
- // $JAVA_HOME/lib/xalan.properties:
- if (propertiesFilename == null) {
- File propertiesFile = null;
- boolean propertiesFileExists = false;
- try {
- String javah = SecuritySupport.getSystemProperty("java.home");
- propertiesFilename = javah + File.separator +
- "lib" + File.separator + DEFAULT_PROPERTIES_FILENAME;
- propertiesFile = new File(propertiesFilename);
- propertiesFileExists = SecuritySupport.getFileExists(propertiesFile);
- } catch (SecurityException e) {
- // try again...
- fLastModified = -1;
- fXalanProperties = null;
- }
-
- synchronized (ObjectFactory.class) {
- boolean loadProperties = false;
- FileInputStream fis = null;
- try {
- // file existed last time
- if(fLastModified >= 0) {
- if(propertiesFileExists &&
- (fLastModified < (fLastModified = SecuritySupport.getLastModified(propertiesFile)))) {
- loadProperties = true;
- } else {
- // file has stopped existing...
- if(!propertiesFileExists) {
- fLastModified = -1;
- fXalanProperties = null;
- } // else, file wasn't modified!
- }
- } else {
- // file has started to exist:
- if(propertiesFileExists) {
- loadProperties = true;
- fLastModified = SecuritySupport.getLastModified(propertiesFile);
- } // else, nothing's changed
- }
- if(loadProperties) {
- // must never have attempted to read xalan.properties
- // before (or it's outdeated)
- fXalanProperties = new Properties();
- fis = SecuritySupport.getFileInputStream(propertiesFile);
- fXalanProperties.load(fis);
- }
- } catch (Exception x) {
- fXalanProperties = null;
- fLastModified = -1;
- // assert(x instanceof FileNotFoundException
- // || x instanceof SecurityException)
- // In both cases, ignore and continue w/ next location
- }
- finally {
- // try to close the input stream if one was opened.
- if (fis != null) {
- try {
- fis.close();
- }
- // Ignore the exception.
- catch (IOException exc) {}
- }
- }
- }
- if(fXalanProperties != null) {
- factoryClassName = fXalanProperties.getProperty(factoryId);
- }
- } else {
- FileInputStream fis = null;
- try {
- fis = SecuritySupport.getFileInputStream(new File(propertiesFilename));
- Properties props = new Properties();
- props.load(fis);
- factoryClassName = props.getProperty(factoryId);
- } catch (Exception x) {
- // assert(x instanceof FileNotFoundException
- // || x instanceof SecurityException)
- // In both cases, ignore and continue w/ next location
- }
- finally {
- // try to close the input stream if one was opened.
- if (fis != null) {
- try {
- fis.close();
- }
- // Ignore the exception.
- catch (IOException exc) {}
- }
- }
- }
- if (factoryClassName != null) {
- if (DEBUG) debugPrintln("found in " + propertiesFilename + ", value="
- + factoryClassName);
- return factoryClassName;
- }
-
- // Try Jar Service Provider Mechanism
- return findJarServiceProviderName(factoryId);
- } // lookUpFactoryClass(String,String):String
-
- //
- // Private static methods
- //
/** Prints a message to standard error if debugging is enabled. */
private static void debugPrintln(String msg) {
if (DEBUG) {
System.err.println("JAXP: " + msg);
@@ -391,11 +56,10 @@
/**
* Figure out which ClassLoader to use. For JDK 1.2 and later use
* the context ClassLoader.
*/
public static ClassLoader findClassLoader()
- throws ConfigurationError
{
if (System.getSecurityManager()!=null) {
//this will ensure bootclassloader is used
return null;
}
@@ -450,12 +114,12 @@
// boot/extension/system ClassLoaders
return context;
} // findClassLoader():ClassLoader
/**
- * Create an instance of a class using the same classloader for the ObjectFactory by default
- * or bootclassloader when Security Manager is in place
+ * Create an instance of a class using the same class loader for the ObjectFactory by default
+ * or boot class loader when Security Manager is in place
*/
public static Object newInstance(String className, boolean doFallback)
throws ConfigurationError
{
if (System.getSecurityManager()!=null) {
@@ -489,14 +153,14 @@
x);
}
}
/**
- * Find a Class using the same classloader for the ObjectFactory by default
- * or bootclassloader when Security Manager is in place
+ * Find a Class using the same class loader for the ObjectFactory by default
+ * or boot class loader when Security Manager is in place
*/
- public static Class findProviderClass(String className, boolean doFallback)
+ public static Class<?> findProviderClass(String className, boolean doFallback)
throws ClassNotFoundException, ConfigurationError
{
if (System.getSecurityManager()!=null) {
return Class.forName(className);
} else {
@@ -506,11 +170,11 @@
}
/**
* Find a Class using the specified ClassLoader
*/
- static Class findProviderClass(String className, ClassLoader cl,
+ private static Class<?> findProviderClass(String className, ClassLoader cl,
boolean doFallback)
throws ClassNotFoundException, ConfigurationError
{
//throw security exception if the calling thread is not allowed to access the
//class. Restrict the access to the package classes as specified in java.security policy.
@@ -529,11 +193,11 @@
}
}catch(SecurityException e){
throw e;
}
- Class providerClass;
+ Class<?> providerClass;
if (cl == null) {
// XXX Use the bootstrap ClassLoader. There is no way to
// load a class using the bootstrap ClassLoader that works
// in both JDK 1.1 and Java 2. However, this should still
// work b/c the following should be true:
@@ -565,95 +229,6 @@
}
return providerClass;
}
- /**
- * Find the name of service provider using Jar Service Provider Mechanism
- *
- * @return instance of provider class if found or null
- */
- private static String findJarServiceProviderName(String factoryId)
- {
- String serviceId = SERVICES_PATH + factoryId;
- InputStream is = null;
-
- // First try the Context ClassLoader
- ClassLoader cl = findClassLoader();
-
- is = SecuritySupport.getResourceAsStream(cl, serviceId);
-
- // If no provider found then try the current ClassLoader
- if (is == null) {
- ClassLoader current = ObjectFactory.class.getClassLoader();
- if (cl != current) {
- cl = current;
- is = SecuritySupport.getResourceAsStream(cl, serviceId);
- }
- }
-
- if (is == null) {
- // No provider found
- return null;
- }
-
- if (DEBUG) debugPrintln("found jar resource=" + serviceId +
- " using ClassLoader: " + cl);
-
- // Read the service provider name in UTF-8 as specified in
- // the jar spec. Unfortunately this fails in Microsoft
- // VJ++, which does not implement the UTF-8
- // encoding. Theoretically, we should simply let it fail in
- // that case, since the JVM is obviously broken if it
- // doesn't support such a basic standard. But since there
- // are still some users attempting to use VJ++ for
- // development, we have dropped in a fallback which makes a
- // second attempt using the platform's default encoding. In
- // VJ++ this is apparently ASCII, which is a subset of
- // UTF-8... and since the strings we'll be reading here are
- // also primarily limited to the 7-bit ASCII range (at
- // least, in English versions), this should work well
- // enough to keep us on the air until we're ready to
- // officially decommit from VJ++. [Edited comment from
- // jkesselm]
- 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;
- try {
- // XXX Does not handle all possible input as specified by the
- // Jar Service Provider specification
- factoryClassName = rd.readLine();
- } catch (IOException x) {
- // No provider found
- return null;
- }
- finally {
- try {
- // try to close the reader.
- rd.close();
- }
- // Ignore the exception.
- catch (IOException exc) {}
- }
-
- if (factoryClassName != null &&
- ! "".equals(factoryClassName)) {
- if (DEBUG) debugPrintln("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 factoryClassName;
- }
-
- // No provider found
- return null;
- }
-
} // class ObjectFactory