diff --git a/java/src/main/java/com/azure/data/cosmos/serialization/hybridrow/SchemaId.java b/java/src/main/java/com/azure/data/cosmos/serialization/hybridrow/SchemaId.java
index 91b1459..ab83ee7 100644
--- a/java/src/main/java/com/azure/data/cosmos/serialization/hybridrow/SchemaId.java
+++ b/java/src/main/java/com/azure/data/cosmos/serialization/hybridrow/SchemaId.java
@@ -14,6 +14,7 @@ import com.fasterxml.jackson.databind.exc.MismatchedInputException;
 import com.fasterxml.jackson.databind.ser.std.StdSerializer;
 import it.unimi.dsi.fastutil.HashCommon;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceMap;
+import it.unimi.dsi.fastutil.ints.Int2ReferenceMaps;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceOpenHashMap;
 
 import javax.annotation.Nonnull;
@@ -38,7 +39,7 @@ public final class SchemaId implements Comparable<SchemaId> {
     private static final Int2ReferenceMap<SchemaId> cache;
 
     static {
-        cache = new Int2ReferenceOpenHashMap<>();
+        cache = Int2ReferenceMaps.synchronize(new Int2ReferenceOpenHashMap<>());
         cache.put(0, INVALID = NONE = new SchemaId(0));
     }
 
diff --git a/java/src/main/java/com/azure/data/cosmos/serialization/hybridrow/layouts/SystemSchema.java b/java/src/main/java/com/azure/data/cosmos/serialization/hybridrow/layouts/SystemSchema.java
index 5cb455f..561dfaf 100644
--- a/java/src/main/java/com/azure/data/cosmos/serialization/hybridrow/layouts/SystemSchema.java
+++ b/java/src/main/java/com/azure/data/cosmos/serialization/hybridrow/layouts/SystemSchema.java
@@ -65,21 +65,12 @@ public final class SystemSchema {
     }
 
     private static InputStream getResourceAsStream(final String name) throws IOException {
+        InputStream inputStream = SystemSchema.class.getClassLoader().getResourceAsStream(name);
 
-        final CodeSource codeSource = SystemSchema.class.getProtectionDomain().getCodeSource();
-        final ClassLoader classLoader = SystemSchema.class.getClassLoader();
-        final String location = codeSource.getLocation().toString();
-        final Enumeration<URL> urls;
-
-        urls = classLoader.getResources(name);
-
-        while (urls.hasMoreElements()) {
-            final URL url = urls.nextElement();
-            if (url.getFile().endsWith(name)) {
-                return url.openStream();
-            }
+        if (inputStream != null) {
+            return inputStream;
         }
 
-        throw new FileNotFoundException(lenientFormat("cannot find %s at %s", name, location));
+        throw new FileNotFoundException(lenientFormat("cannot find %s", name));
     }
 }