Fix matching file prefixes for FILE based catalogs (#505)

polaris-core/src/main/java/org/apache/polaris/core/storage/StorageLocation.java

@@ -25,6 +25,7 @@
 /** An abstraction over a storage location */
 public class StorageLocation {
   private final String location;
+  public static final String LOCAL_PATH_PREFIX = "file:///";
 
   /** Create a StorageLocation from a String path */
   public static StorageLocation of(String location) {
@@ -39,8 +40,10 @@ public static StorageLocation of(String location) {
   protected StorageLocation(@Nonnull String location) {
     if (location == null) {
       this.location = null;
-    } else if (location.startsWith("file:/") && !location.startsWith("file:///")) {
-      this.location = URI.create(location.replaceFirst("file:/+", "file:///")).toString();
+    } else if (location.startsWith("file:/") && !location.startsWith(LOCAL_PATH_PREFIX)) {
+      this.location = URI.create(location.replaceFirst("file:/+", LOCAL_PATH_PREFIX)).toString();
+    } else if (location.startsWith("/")) {
+      this.location = URI.create(location.replaceFirst("/+", LOCAL_PATH_PREFIX)).toString();
     } else {
       this.location = URI.create(location).toString();
     }

polaris-core/src/test/java/org/apache/polaris/service/storage/StorageLocationTest.java

@@ -0,0 +1,35 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.polaris.service.storage;
+
+import org.apache.polaris.core.storage.StorageLocation;
+import org.assertj.core.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+public class StorageLocationTest {
+
+  @Test
+  public void testOfDifferentPrefixes() {
+    StorageLocation StandardLocation = StorageLocation.of("file:///path/to/file");
+    StorageLocation slashLeadingLocation = StorageLocation.of("/path/to/file");
+    StorageLocation fileSingleSlashLocation = StorageLocation.of("file:/path/to/file");
+    Assertions.assertThat(slashLeadingLocation.equals(StandardLocation)).isTrue();
+    Assertions.assertThat(fileSingleSlashLocation.equals(StandardLocation)).isTrue();
+  }
+}