Use try-with-resources

- Don't hide exceptions on internal close()
- Use generics
- Remove now unnecessary @SuppressWarnings

Author: garydgregory

src/main/java/org/apache/commons/dbcp2/datasources/InstanceKeyDataSourceFactory.java

@@ -24,7 +24,6 @@
 import java.util.Hashtable;
 import java.util.List;
 import java.util.Map;
-import java.util.Properties;
 import java.util.concurrent.ConcurrentHashMap;
 
 import javax.naming.Context;
@@ -74,22 +73,16 @@ public static void closeAll() throws ListException {
     /**
      * Deserializes the provided byte array to create an object.
      *
-     * @param data
-     *            Data to deserialize to create the configuration parameter.
-     *
+     * @param <T>  The type of the object to be deserialized.
+     * @param data Data to deserialize to create the configuration parameter.
      * @return The Object created by deserializing the data.
-     * @throws ClassNotFoundException
-     *            If a class cannot be found during the deserialization of a configuration parameter.
-     * @throws IOException
-     *            If an I/O error occurs during the deserialization of a configuration parameter.
+     * @throws ClassNotFoundException If a class cannot be found during the deserialization of a configuration parameter.
+     * @throws IOException            If an I/O error occurs during the deserialization of a configuration parameter.
      */
-    protected static final Object deserialize(final byte[] data) throws IOException, ClassNotFoundException {
-        ObjectInputStream in = null;
-        try {
-            in = new ObjectInputStream(new ByteArrayInputStream(data));
-            return in.readObject();
-        } finally {
-            Utils.closeQuietly(in);
+    @SuppressWarnings("unchecked") // call site must ensure that the type is correct
+    protected static final <T> T deserialize(final byte[] data) throws IOException, ClassNotFoundException {
+        try (ObjectInputStream in = new ObjectInputStream(new ByteArrayInputStream(data))) {
+            return (T) in.readObject();
         }
     }
 
@@ -216,7 +209,7 @@ private void setCommonProperties(final Reference ref, final InstanceKeyDataSourc
         refAddr = ref.get("jndiEnvironment");
         if (hasContent(refAddr)) {
             final byte[] serialized = (byte[]) refAddr.getContent();
-            ikds.setJndiEnvironment((Properties) deserialize(serialized));
+            ikds.setJndiEnvironment(deserialize(serialized));
         }
 
         refAddr = ref.get("loginTimeout");

src/main/java/org/apache/commons/dbcp2/datasources/PerUserPoolDataSourceFactory.java

@@ -18,7 +18,6 @@
 
 import java.io.IOException;
 import java.time.Duration;
-import java.util.Map;
 
 import javax.naming.RefAddr;
 import javax.naming.Reference;
@@ -32,13 +31,12 @@ public class PerUserPoolDataSourceFactory extends InstanceKeyDataSourceFactory {
     private static final String PER_USER_POOL_CLASSNAME = PerUserPoolDataSource.class.getName();
 
     /**
-     * Constructs a new instance.
+     * Constructs a new instance.Ωø∂
      */
     public PerUserPoolDataSourceFactory() {
         // empty
     }
 
-    @SuppressWarnings("unchecked") // Avoid warnings on deserialization
     @Override
     protected InstanceKeyDataSource getNewInstance(final Reference ref) throws IOException, ClassNotFoundException {
         final PerUserPoolDataSource pupds = new PerUserPoolDataSource();
@@ -60,37 +58,37 @@ protected InstanceKeyDataSource getNewInstance(final Reference ref) throws IOExc
         refAddr = ref.get("perUserDefaultAutoCommit");
         if (refAddr != null && refAddr.getContent() != null) {
             final byte[] serialized = (byte[]) refAddr.getContent();
-            pupds.setPerUserDefaultAutoCommit((Map<String, Boolean>) deserialize(serialized));
+            pupds.setPerUserDefaultAutoCommit(deserialize(serialized));
         }
 
         refAddr = ref.get("perUserDefaultTransactionIsolation");
         if (refAddr != null && refAddr.getContent() != null) {
             final byte[] serialized = (byte[]) refAddr.getContent();
-            pupds.setPerUserDefaultTransactionIsolation((Map<String, Integer>) deserialize(serialized));
+            pupds.setPerUserDefaultTransactionIsolation(deserialize(serialized));
         }
 
         refAddr = ref.get("perUserMaxTotal");
         if (refAddr != null && refAddr.getContent() != null) {
             final byte[] serialized = (byte[]) refAddr.getContent();
-            pupds.setPerUserMaxTotal((Map<String, Integer>) deserialize(serialized));
+            pupds.setPerUserMaxTotal(deserialize(serialized));
         }
 
         refAddr = ref.get("perUserMaxIdle");
         if (refAddr != null && refAddr.getContent() != null) {
             final byte[] serialized = (byte[]) refAddr.getContent();
-            pupds.setPerUserMaxIdle((Map<String, Integer>) deserialize(serialized));
+            pupds.setPerUserMaxIdle(deserialize(serialized));
         }
 
         refAddr = ref.get("perUserMaxWaitMillis");
         if (refAddr != null && refAddr.getContent() != null) {
             final byte[] serialized = (byte[]) refAddr.getContent();
-            pupds.setPerUserMaxWaitMillis((Map<String, Long>) deserialize(serialized));
+            pupds.setPerUserMaxWaitMillis(deserialize(serialized));
         }
 
         refAddr = ref.get("perUserDefaultReadOnly");
         if (refAddr != null && refAddr.getContent() != null) {
             final byte[] serialized = (byte[]) refAddr.getContent();
-            pupds.setPerUserDefaultReadOnly((Map<String, Boolean>) deserialize(serialized));
+            pupds.setPerUserDefaultReadOnly(deserialize(serialized));
         }
         return pupds;
     }