#1604 - Open URL resources without caching

src/main/java/io/ebeaninternal/server/core/DScriptRunner.java

@@ -4,6 +4,7 @@ import io.ebean.ScriptRunner;
 import io.ebean.migration.ddl.DdlRunner;
 import io.ebean.migration.runner.ScriptTransform;
 import io.ebeaninternal.api.SpiEbeanServer;
+import io.ebeaninternal.util.UrlHelper;
 
 import javax.persistence.PersistenceException;
 import java.io.IOException;
@@ -63,7 +64,7 @@ class DScriptRunner implements ScriptRunner {
       throw new IllegalArgumentException("resource is null?");
     }
 
-    try (InputStream inputStream = resource.openStream()) {
+    try (InputStream inputStream = UrlHelper.openNoCache(resource)) {
       return readContent(new InputStreamReader(inputStream));
 
     } catch (IOException e) {

src/main/java/io/ebeaninternal/server/core/bootup/ManifestReader.java

@@ -1,6 +1,7 @@
 package io.ebeaninternal.server.core.bootup;
 
 import io.ebean.util.StringHelper;
+import io.ebeaninternal.util.UrlHelper;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -59,7 +60,7 @@ class ManifestReader {
     try {
       Enumeration<URL> resources = classLoader.getResources(resourcePath);
       while (resources.hasMoreElements()) {
-        try (InputStream is = resources.nextElement().openStream()) {
+        try (InputStream is = UrlHelper.openNoCache(resources.nextElement())) {
           read(new Manifest(is));
         }
       }

src/main/java/io/ebeaninternal/util/UrlHelper.java

@@ -0,0 +1,22 @@
+package io.ebeaninternal.util;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URL;
+import java.net.URLConnection;
+
+/**
+ * Helper to open URL content without file descriptor caching (by underlying JDK JarURLConnection).
+ */
+public class UrlHelper {
+
+  /**
+   * Open the URL content without using caching returning the resulting InputStream.
+   */
+  public static InputStream openNoCache(URL url) throws IOException {
+
+    URLConnection urlConnection = url.openConnection();
+    urlConnection.setUseCaches(false);
+    return urlConnection.getInputStream();
+  }
+}

src/main/java/io/ebeaninternal/xmlmapping/XmlMappingReader.java

@@ -1,5 +1,6 @@
 package io.ebeaninternal.xmlmapping;
 
+import io.ebeaninternal.util.UrlHelper;
 import io.ebeaninternal.xmlmapping.model.XmEbean;
 import org.avaje.classpath.scanner.Resource;
 
@@ -41,7 +42,7 @@ public class XmlMappingReader {
       List<XmEbean> mappings = new ArrayList<>();
       while (resources.hasMoreElements()) {
         URL url = resources.nextElement();
-        try (InputStream is = url.openStream()) {
+        try (InputStream is = UrlHelper.openNoCache(url)) {
           mappings.add(XmlMappingReader.read(is));
         }
       }