diff --git a/src/main/java/net/fortuna/ical4j/model/TimeZoneLoader.java b/src/main/java/net/fortuna/ical4j/model/TimeZoneLoader.java
index e91883496..12e3bad62 100644
--- a/src/main/java/net/fortuna/ical4j/model/TimeZoneLoader.java
+++ b/src/main/java/net/fortuna/ical4j/model/TimeZoneLoader.java
@@ -14,6 +14,7 @@
 import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
+import java.io.InputStream;
 import java.net.InetSocketAddress;
 import java.net.Proxy;
 import java.net.URL;
@@ -99,15 +100,17 @@ public VTimeZone loadVTimeZone(String id) throws IOException, ParserException, P
         if (!cache.containsId(id)) {
             final URL resource = ResourceLoader.getResource(resourcePrefix + id + ".ics");
             if (resource != null) {
-                final CalendarBuilder builder = new CalendarBuilder();
-                final Calendar calendar = builder.build(resource.openStream());
-                final VTimeZone vTimeZone = (VTimeZone) calendar.getComponent(Component.VTIMEZONE);
-                // load any available updates for the timezone.. can be explicility disabled via configuration
-                if (!"false".equals(Configurator.getProperty(UPDATE_ENABLED).orElse("true"))) {
-                    return updateDefinition(vTimeZone);
-                }
-                if (vTimeZone != null) {
-                    cache.putIfAbsent(id, vTimeZone);
+                try (InputStream in = resource.openStream()) {
+                    final CalendarBuilder builder = new CalendarBuilder();
+                    final Calendar calendar = builder.build(in);
+                    final VTimeZone vTimeZone = (VTimeZone) calendar.getComponent(Component.VTIMEZONE);
+                    // load any available updates for the timezone.. can be explicility disabled via configuration
+                    if (!"false".equals(Configurator.getProperty(UPDATE_ENABLED).orElse("true"))) {
+                        return updateDefinition(vTimeZone);
+                    }
+                    if (vTimeZone != null) {
+                        cache.putIfAbsent(id, vTimeZone);
+                    }
                 }
             } else {
                 return generateTimezoneForId(id);
diff --git a/src/main/java/net/fortuna/ical4j/util/Configurator.java b/src/main/java/net/fortuna/ical4j/util/Configurator.java
index 77f882953..0d6815876 100644
--- a/src/main/java/net/fortuna/ical4j/util/Configurator.java
+++ b/src/main/java/net/fortuna/ical4j/util/Configurator.java
@@ -35,6 +35,7 @@
 import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
+import java.io.InputStream;
 import java.util.Optional;
 import java.util.Properties;
 
@@ -55,8 +56,8 @@ public final class Configurator {
     private static final Properties CONFIG = new Properties();
 
     static {
-        try {
-            CONFIG.load(ResourceLoader.getResourceAsStream("ical4j.properties"));
+        try (InputStream in = ResourceLoader.getResourceAsStream("ical4j.properties")) {
+            CONFIG.load(in);
         } catch (IOException | NullPointerException e) {
             LOG.info("ical4j.properties not found.");
         }