close every registered Closeable, instead of explicitly close a special set of instances

scm-webapp/src/main/java/sonia/scm/CloseableModule.java

@@ -0,0 +1,56 @@
+package sonia.scm;
+
+import com.google.inject.AbstractModule;
+import com.google.inject.TypeLiteral;
+import com.google.inject.spi.InjectionListener;
+import com.google.inject.spi.TypeEncounter;
+import com.google.inject.spi.TypeListener;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import sonia.scm.util.IOUtil;
+
+import java.io.Closeable;
+import java.lang.ref.WeakReference;
+import java.util.Deque;
+import java.util.concurrent.ConcurrentLinkedDeque;
+
+public final class CloseableModule extends AbstractModule {
+
+  private static final Logger LOG = LoggerFactory.getLogger(CloseableModule.class);
+
+  private final Deque<WeakReference<Closeable>> closeables = new ConcurrentLinkedDeque<>();
+
+  @Override
+  protected void configure() {
+    bindListener(MoreMatchers.isSubtypeOf(Closeable.class), new TypeListener() {
+      @Override
+      public <I> void hear(TypeLiteral<I> type, TypeEncounter<I> encounter) {
+        encounter.register((InjectionListener<I>) instance -> {
+          LOG.debug("register closable {}", instance.getClass());
+          Closeable closeable = (Closeable) instance;
+          closeables.push(new WeakReference<>(closeable));
+        });
+      }
+    });
+
+    bind(CloseableModule.class).toInstance(this);
+  }
+
+  public void closeAll() {
+    LOG.debug("close all registered closeables");
+    WeakReference<Closeable> reference = closeables.poll();
+    while (reference != null) {
+      Closeable closeable = reference.get();
+      close(closeable);
+      reference = closeables.poll();
+    }
+  }
+
+  private void close(Closeable closeable) {
+    if (closeable != null) {
+      LOG.trace("close closeable instance of {}", closeable);
+      IOUtil.close(closeable);
+    }
+  }
+
+}