When processing META-INF/services SchemaFactoryFinder was calling

loadFromProperty() which reads a META-INF/services file as if it were a
properties file. In SchemaFactory [1] for the META-INF/services file it
says to look at the "JAR file specification for file format and parsing
rules". Looking at the JAR file specification [2] it says: "The file
should contain a newline-separated list of unique concrete provider-class
names".

We should now be reading the META-INF/services files as specified
in the JAR file specification.

[1] http://java.sun.com/j2se/1.5.0/docs/api/javax/xml/validation/SchemaFactory.html#newInstance(java.lang.String)
[2] http://java.sun.com/j2se/1.5.0/docs/guide/jar/jar.html#Provider%20Configuration%20File


git-svn-id: https://svn.apache.org/repos/asf/xml/commons/trunk@226247 13f79535-47bb-0310-9956-ffa450edef68

java/external/src/javax/xml/validation/SchemaFactoryFinder.java

@@ -17,9 +17,11 @@
 
 package javax.xml.validation;
 
+import java.io.BufferedReader;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
+import java.io.InputStreamReader;
 import java.net.URL;
 import java.util.ArrayList;
 import java.util.Enumeration;
@@ -52,6 +54,11 @@ class SchemaFactoryFinder  {
 	 */
 	private static boolean firstTime = true;
     
+    /**
+     * Default columns per line.
+     */
+    private static final int DEFAULT_LINE_LENGTH = 80;
+    
     static {
         // Use try/catch block to support applets
         try {
@@ -146,7 +153,6 @@ class SchemaFactoryFinder  {
      */
     private SchemaFactory _newFactory(String schemaLanguage) {
         SchemaFactory sf;
-        
         String propertyName = SERVICE_CLASS.getName() + ":" + schemaLanguage;
         
         // system property look up
@@ -229,8 +235,7 @@ class SchemaFactoryFinder  {
             URL resource = (URL)sitr.next();
             debugPrintln("looking into " + resource);
             try {
-                //sf = loadFromProperty(schemaLanguage,resource.toExternalForm(),resource.openStream());
+                sf = loadFromServicesFile(schemaLanguage,resource.toExternalForm(),ss.getURLInputStream(resource));
-                sf = loadFromProperty(schemaLanguage,resource.toExternalForm(),ss.getURLInputStream(resource));
                 if(sf!=null)    return sf;
             } catch(IOException e) {
                 if( debug ) {
@@ -363,6 +368,84 @@ class SchemaFactoryFinder  {
         }
     }
     
+    /** Searches for a SchemaFactory for a given schema language in a META-INF/services file. */
+    private SchemaFactory loadFromServicesFile(String schemaLanguage, String resourceName, InputStream in) {
+
+        debugPrintln("Reading "+resourceName );
+        
+        // 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(in, "UTF-8"), DEFAULT_LINE_LENGTH);
+        } catch (java.io.UnsupportedEncodingException e) {
+            rd = new BufferedReader(new InputStreamReader(in), DEFAULT_LINE_LENGTH);
+        }
+        
+        String factoryClassName = null;
+        SchemaFactory resultFactory = null;
+        // See spec for provider-configuration files: http://java.sun.com/j2se/1.5.0/docs/guide/jar/jar.html#Provider%20Configuration%20File
+        while (true) {
+            try {
+                factoryClassName = rd.readLine();   
+            } catch (IOException x) {
+                // No provider found
+                break;
+            }
+            if (factoryClassName != null) {
+                // Ignore comments in the provider-configuration file
+                int hashIndex = factoryClassName.indexOf('#');
+                if (hashIndex != -1) {
+                    factoryClassName = factoryClassName.substring(0, hashIndex);
+                }
+                
+                // Ignore leading and trailing whitespace
+                factoryClassName = factoryClassName.trim();
+                
+                // If there's no text left or if this was a blank line, go to the next one.
+                if (factoryClassName.length() == 0) {
+                    continue;
+                }
+                
+                try {
+                    // Found the right SchemaFactory if its isSchemaLanguageSupported(schemaLanguage) method returns true.
+                    SchemaFactory foundFactory = (SchemaFactory) createInstance(factoryClassName);
+                    if (foundFactory.isSchemaLanguageSupported(schemaLanguage)) {
+                        resultFactory = foundFactory;
+                        break;
+                    }
+                }
+                catch (Exception e) {}
+            }
+            else {
+                break;
+            }
+        }
+        
+        try {
+            // try to close the reader.
+            rd.close();
+        }
+        // Ignore the exception.
+        catch (IOException exc) {}
+        
+        return resultFactory;
+    }
+    
     private static final Class SERVICE_CLASS = SchemaFactory.class;
     private static final String SERVICE_ID = "META-INF/services/" + SERVICE_CLASS.getName();