Introduce CloseableUtil

resources/smacklint.sh

@@ -0,0 +1,3 @@
+#!/usr/bin/env bash
+
+find smack-integration-test -type f -path "*/src/main/java/*/smackx/*/package-info.java"

smack-bosh/src/main/java/org/jivesoftware/smack/bosh/XMPPBOSHConnection.java

@@ -41,6 +41,7 @@ import org.jivesoftware.smack.packet.Stanza;
 import org.jivesoftware.smack.packet.StanzaError;
 import org.jivesoftware.smack.sasl.packet.SaslStreamElements.SASLFailure;
 import org.jivesoftware.smack.sasl.packet.SaslStreamElements.Success;
+import org.jivesoftware.smack.util.CloseableUtil;
 import org.jivesoftware.smack.util.PacketParserUtils;
 
 import org.igniterealtime.jbosh.AbstractBody;
@@ -261,28 +262,13 @@ public class XMPPBOSHConnection extends AbstractXMPPConnection {
         isFirstInitialization = false;
 
         // Close down the readers and writers.
-        if (readerPipe != null) {
-            try {
-                readerPipe.close();
-            }
-            catch (Throwable ignore) { /* ignore */ }
-            reader = null;
-        }
-        if (reader != null) {
-            try {
-                reader.close();
-            }
-            catch (Throwable ignore) { /* ignore */ }
-            reader = null;
-        }
-        if (writer != null) {
-            try {
-                writer.close();
-            }
-            catch (Throwable ignore) { /* ignore */ }
-            writer = null;
-        }
+        CloseableUtil.maybeClose(readerPipe, LOGGER);
+        CloseableUtil.maybeClose(reader, LOGGER);
+        CloseableUtil.maybeClose(writer, LOGGER);
 
+        readerPipe = null;
+        reader = null;
+        writer = null;
         readerConsumer = null;
     }
 

smack-core/src/main/java/org/jivesoftware/smack/SmackInitialization.java

@@ -18,7 +18,6 @@
 package org.jivesoftware.smack;
 
 import java.io.BufferedReader;
-import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.util.Collection;
@@ -37,6 +36,7 @@ import org.jivesoftware.smack.sasl.core.SASLAnonymous;
 import org.jivesoftware.smack.sasl.core.SASLXOauth2Mechanism;
 import org.jivesoftware.smack.sasl.core.SCRAMSHA1Mechanism;
 import org.jivesoftware.smack.sasl.core.ScramSha1PlusMechanism;
+import org.jivesoftware.smack.util.CloseableUtil;
 import org.jivesoftware.smack.util.FileUtils;
 import org.jivesoftware.smack.util.StringUtils;
 
@@ -61,17 +61,15 @@ public final class SmackInitialization {
      */
     static {
         String smackVersion;
+        BufferedReader reader = null;
         try {
-            BufferedReader reader = new BufferedReader(new InputStreamReader(FileUtils.getStreamForClasspathFile("org.jivesoftware.smack/version", null), StringUtils.UTF8));
+            reader = new BufferedReader(new InputStreamReader(FileUtils.getStreamForClasspathFile("org.jivesoftware.smack/version", null), StringUtils.UTF8));
             smackVersion = reader.readLine();
-            try {
-                reader.close();
-            } catch (IOException e) {
-                LOGGER.log(Level.WARNING, "IOException closing stream", e);
-            }
         } catch (Exception e) {
             LOGGER.log(Level.SEVERE, "Could not determine Smack version", e);
             smackVersion = "unknown";
+        } finally {
+            CloseableUtil.maybeClose(reader, LOGGER);
         }
         SMACK_VERSION = smackVersion;
 
@@ -146,12 +144,7 @@ public final class SmackInitialization {
             eventType = parser.next();
         }
         while (eventType != XmlPullParser.END_DOCUMENT);
-        try {
-            cfgFileStream.close();
-        }
-        catch (IOException e) {
-            LOGGER.log(Level.SEVERE, "Error while closing config file input stream", e);
-        }
+        CloseableUtil.maybeClose(cfgFileStream, LOGGER);
     }
 
     private static void parseClassesToLoad(XmlPullParser parser, boolean optional,

smack-core/src/main/java/org/jivesoftware/smack/initializer/UrlInitializer.java

@@ -16,7 +16,6 @@
  */
 package org.jivesoftware.smack.initializer;
 
-import java.io.IOException;
 import java.io.InputStream;
 import java.net.URI;
 import java.util.LinkedList;
@@ -27,6 +26,7 @@ import java.util.logging.Logger;
 import org.jivesoftware.smack.SmackInitialization;
 import org.jivesoftware.smack.provider.ProviderFileLoader;
 import org.jivesoftware.smack.provider.ProviderManager;
+import org.jivesoftware.smack.util.CloseableUtil;
 import org.jivesoftware.smack.util.FileUtils;
 
 /**
@@ -86,14 +86,6 @@ public abstract class UrlInitializer implements SmackInitializer {
     }
 
     private static void maybeClose(InputStream is) {
-        if (is == null) {
-            return;
-        }
-        try {
-            is.close();
-        }
-        catch (IOException e) {
-            LOGGER.log(Level.WARNING, "Could not close input stream", e);
-        }
+        CloseableUtil.maybeClose(is, LOGGER);
     }
 }

smack-core/src/main/java/org/jivesoftware/smack/provider/ProviderFileLoader.java

@@ -26,6 +26,7 @@ import java.util.logging.Logger;
 
 import org.jivesoftware.smack.packet.ExtensionElement;
 import org.jivesoftware.smack.packet.IQ;
+import org.jivesoftware.smack.util.CloseableUtil;
 
 import org.xmlpull.v1.XmlPullParser;
 import org.xmlpull.v1.XmlPullParserFactory;
@@ -141,12 +142,7 @@ public class ProviderFileLoader implements ProviderLoader {
             exceptions.add(e);
         }
         finally {
-            try {
-                providerStream.close();
-            }
-            catch (Exception e) {
-                LOGGER.log(Level.WARNING, "Exception closing provider stream", e);
-            }
+            CloseableUtil.maybeClose(providerStream, LOGGER);
         }
     }
 

smack-core/src/main/java/org/jivesoftware/smack/proxy/Socks5ProxySocketConnection.java

@@ -21,7 +21,9 @@ import java.io.InputStream;
 import java.io.OutputStream;
 import java.net.InetSocketAddress;
 import java.net.Socket;
+import java.util.logging.Logger;
 
+import org.jivesoftware.smack.util.CloseableUtil;
 import org.jivesoftware.smack.util.StringUtils;
 
 /**
@@ -30,6 +32,8 @@ import org.jivesoftware.smack.util.StringUtils;
  * @author Atul Aggarwal
  */
 public class Socks5ProxySocketConnection implements ProxySocketConnection {
+    private static final Logger LOGGER = Logger.getLogger(Socks5ProxySocketConnection.class.getName());
+
     private final ProxyInfo proxy;
 
     Socks5ProxySocketConnection(ProxyInfo proxy) {
@@ -164,11 +168,7 @@ public class Socks5ProxySocketConnection implements ProxySocketConnection {
             }
 
             if (!check) {
-                try {
-                    socket.close();
-                }
-                catch (Exception eee) {
-                }
+                CloseableUtil.maybeClose(socket, LOGGER);
                 throw new ProxyException(ProxyInfo.ProxyType.SOCKS5,
                     "fail in SOCKS5 proxy");
             }
@@ -253,11 +253,7 @@ public class Socks5ProxySocketConnection implements ProxySocketConnection {
             fill(in, buf, 4);
 
             if (buf[1] != 0) {
-                try {
-                    socket.close();
-                }
-                catch (Exception eee) {
-                }
+                CloseableUtil.maybeClose(socket, LOGGER);
                 throw new ProxyException(ProxyInfo.ProxyType.SOCKS5,
                     "server returns " + buf[1]);
             }
@@ -280,11 +276,7 @@ public class Socks5ProxySocketConnection implements ProxySocketConnection {
             throw e;
         }
         catch (Exception e) {
-            try {
-                socket.close();
-            }
-            catch (Exception eee) {
-            }
+            CloseableUtil.maybeClose(socket, LOGGER);
             // TODO convert to IOException(e) when minimum Android API level is 9 or higher
             throw new IOException(e.getLocalizedMessage());
         }

smack-core/src/main/java/org/jivesoftware/smack/util/CloseableUtil.java

@@ -0,0 +1,37 @@
+/**
+ *
+ * Copyright 2018 Florian Schmaus
+ *
+ * Licensed 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.jivesoftware.smack.util;
+
+import java.io.Closeable;
+import java.io.IOException;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+public class CloseableUtil {
+
+    public static void maybeClose(Closeable closable, Logger logger) {
+        if (closable == null) {
+            return;
+        }
+
+        try {
+            closable.close();
+        } catch (IOException e) {
+            logger.log(Level.WARNING, "Could not close " + closable, e);
+        }
+    }
+}

smack-extensions/src/main/java/org/jivesoftware/smackx/bytestreams/socks5/Socks5Client.java

@@ -29,11 +29,11 @@ import java.util.concurrent.ExecutionException;
 import java.util.concurrent.FutureTask;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
-import java.util.logging.Level;
 import java.util.logging.Logger;
 
 import org.jivesoftware.smack.SmackException;
 import org.jivesoftware.smack.XMPPException;
+import org.jivesoftware.smack.util.CloseableUtil;
 import org.jivesoftware.smack.util.StringUtils;
 import org.jivesoftware.smackx.bytestreams.socks5.packet.Bytestream.StreamHost;
 
@@ -97,11 +97,7 @@ public class Socks5Client {
                 }
                 catch (SmackException e) {
                     if (!socket.isClosed()) {
-                        try {
-                            socket.close();
-                        } catch (IOException e2) {
-                            LOGGER.log(Level.WARNING, "Could not close SOCKS5 socket", e2);
-                        }
+                        CloseableUtil.maybeClose(socket, LOGGER);
                     }
                     throw e;
                 }

smack-extensions/src/main/java/org/jivesoftware/smackx/bytestreams/socks5/Socks5Proxy.java

@@ -38,6 +38,7 @@ import java.util.logging.Level;
 import java.util.logging.Logger;
 
 import org.jivesoftware.smack.SmackException;
+import org.jivesoftware.smack.util.CloseableUtil;
 import org.jivesoftware.smack.util.StringUtils;
 
 /**
@@ -409,14 +410,7 @@ public final class Socks5Proxy {
                      */
                 }
                 catch (Exception e) {
-                    try {
-                        if (socket != null) {
-                            socket.close();
-                        }
-                    }
-                    catch (IOException e1) {
-                        /* do nothing */
-                    }
+                    CloseableUtil.maybeClose(socket, LOGGER);
                 }
             }
 

smack-extensions/src/main/java/org/jivesoftware/smackx/filetransfer/IncomingFileTransfer.java

@@ -27,12 +27,12 @@ import java.util.concurrent.ExecutionException;
 import java.util.concurrent.FutureTask;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
-import java.util.logging.Level;
 import java.util.logging.Logger;
 
 import org.jivesoftware.smack.SmackException;
 import org.jivesoftware.smack.SmackException.NoResponseException;
 import org.jivesoftware.smack.XMPPException.XMPPErrorException;
+import org.jivesoftware.smack.util.CloseableUtil;
 
 
 /**
@@ -158,20 +158,8 @@ public class IncomingFileTransfer extends FileTransfer {
                 if (getStatus().equals(Status.in_progress)) {
                     setStatus(Status.complete);
                 }
-                if (inputStream != null) {
-                    try {
-                        inputStream.close();
-                    } catch (IOException e) {
-                        LOGGER.log(Level.WARNING, "Closing input stream", e);
-                    }
-                }
-                if (outputStream != null) {
-                    try {
-                        outputStream.close();
-                    } catch (IOException e) {
-                        LOGGER.log(Level.WARNING, "Closing output stream", e);
-                    }
-                }
+                CloseableUtil.maybeClose(inputStream, LOGGER);
+                CloseableUtil.maybeClose(outputStream, LOGGER);
             }
         }, "File Transfer " + streamID);
         transferThread.start();

smack-extensions/src/main/java/org/jivesoftware/smackx/filetransfer/OutgoingFileTransfer.java

@@ -22,7 +22,6 @@ import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
-import java.util.logging.Level;
 import java.util.logging.Logger;
 
 import org.jivesoftware.smack.SmackException;
@@ -30,6 +29,7 @@ import org.jivesoftware.smack.SmackException.IllegalStateChangeException;
 import org.jivesoftware.smack.XMPPException;
 import org.jivesoftware.smack.XMPPException.XMPPErrorException;
 import org.jivesoftware.smack.packet.StanzaError;
+import org.jivesoftware.smack.util.CloseableUtil;
 
 import org.jxmpp.jid.Jid;
 
@@ -258,19 +258,8 @@ public class OutgoingFileTransfer extends FileTransfer {
                     setStatus(FileTransfer.Status.error);
                     setException(e);
                 } finally {
-                        if (inputStream != null) {
-                            try {
-                                inputStream.close();
-                            } catch (IOException e) {
-                                LOGGER.log(Level.WARNING, "Closing input stream", e);
-                            }
-                        }
-
-                        try {
-                            outputStream.close();
-                        } catch (IOException e) {
-                            LOGGER.log(Level.WARNING, "Closing output stream", e);
-                        }
+                    CloseableUtil.maybeClose(inputStream, LOGGER);
+                    CloseableUtil.maybeClose(outputStream, LOGGER);
                 }
                 updateStatus(Status.in_progress, FileTransfer.Status.complete);
                 }
@@ -325,16 +314,8 @@ public class OutgoingFileTransfer extends FileTransfer {
                     setStatus(FileTransfer.Status.error);
                     setException(e);
                 } finally {
-                    try {
-                        if (in != null) {
-                            in.close();
-                        }
-
-                        outputStream.flush();
-                        outputStream.close();
-                    } catch (IOException e) {
-                        /* Do Nothing */
-                    }
+                    CloseableUtil.maybeClose(in, LOGGER);
+                    CloseableUtil.maybeClose(outputStream, LOGGER);
                 }
                 updateStatus(Status.in_progress, FileTransfer.Status.complete);
                 }

smack-extensions/src/main/java/org/jivesoftware/smackx/jiveproperties/packet/JivePropertiesExtension.java

@@ -29,6 +29,7 @@ import java.util.logging.Logger;
 
 import org.jivesoftware.smack.packet.ExtensionElement;
 import org.jivesoftware.smack.packet.Message;
+import org.jivesoftware.smack.util.CloseableUtil;
 import org.jivesoftware.smack.util.XmlStringBuilder;
 import org.jivesoftware.smack.util.stringencoder.Base64;
 
@@ -191,22 +192,8 @@ public class JivePropertiesExtension implements ExtensionElement {
                     valueStr = "Serializing error: " + e.getMessage();
                 }
                 finally {
-                    if (out != null) {
-                        try {
-                            out.close();
-                        }
-                        catch (Exception e) {
-                            // Ignore.
-                        }
-                    }
-                    if (byteStream != null) {
-                        try {
-                            byteStream.close();
-                        }
-                        catch (Exception e) {
-                            // Ignore.
-                        }
-                    }
+                    CloseableUtil.maybeClose(out, LOGGER);
+                    CloseableUtil.maybeClose(byteStream, LOGGER);
                 }
             }
             xml.attribute("type", type);

smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/FileBasedOmemoStore.java

@@ -35,6 +35,8 @@ import java.util.TreeSet;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
+import org.jivesoftware.smack.util.CloseableUtil;
+
 import org.jivesoftware.smackx.omemo.exceptions.CorruptedOmemoKeyException;
 import org.jivesoftware.smackx.omemo.internal.OmemoCachedDeviceList;
 import org.jivesoftware.smackx.omemo.internal.OmemoDevice;
@@ -417,15 +419,8 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
 
         } catch (IOException e) {
             LOGGER.log(Level.SEVERE, "Could not write longs to file.", e);
-
         } finally {
-            if (out != null) {
-                try {
-                    out.close();
-                } catch (IOException e) {
-                    LOGGER.log(Level.SEVERE, "Could not close OutputStream.", e);
-                }
-            }
+            CloseableUtil.maybeClose(out, LOGGER);
         }
     }
 
@@ -447,13 +442,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
             LOGGER.log(Level.SEVERE, "Could not read long from file.", e);
             return null;
         } finally {
-            if (in != null) {
-                try {
-                    in.close();
-                } catch (IOException e) {
-                    LOGGER.log(Level.SEVERE, "Could not close InputStream.", e);
-                }
-            }
+            CloseableUtil.maybeClose(in, LOGGER);
         }
 
         return l;
@@ -481,15 +470,8 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
 
         } catch (IOException e) {
             LOGGER.log(Level.SEVERE, "Could not write bytes to file.", e);
-
         } finally {
-            if (out != null) {
-                try {
-                    out.close();
-                } catch (IOException e) {
-                    LOGGER.log(Level.SEVERE, "Could not close OutputStream.", e);
-                }
-            }
+            CloseableUtil.maybeClose(out, LOGGER);
         }
     }
 
@@ -510,15 +492,8 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
             b = null;
         } catch (IOException e) {
             LOGGER.log(Level.SEVERE, "Could not read bytes from file.", e);
-
         } finally {
-            if (in != null) {
-                try {
-                    in.close();
-                } catch (IOException e) {
-                    LOGGER.log(Level.SEVERE, "Could not close InputStream.", e);
-                }
-            }
+            CloseableUtil.maybeClose(in, LOGGER);
         }
 
         return b;
@@ -540,15 +515,8 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
 
         } catch (IOException e) {
             LOGGER.log(Level.SEVERE, "Could not write integers to file.", e);
-
         } finally {
-            if (out != null) {
-                try {
-                    out.close();
-                } catch (IOException e) {
-                    LOGGER.log(Level.SEVERE, "Could not close OutputStream.", e);
-                }
-            }
+            CloseableUtil.maybeClose(out, LOGGER);
         }
     }
 
@@ -577,13 +545,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
         } catch (IOException e) {
             LOGGER.log(Level.SEVERE, "Could not read integers.", e);
         } finally {
-            if (in != null) {
-                try {
-                    in.close();
-                } catch (IOException e) {
-                    LOGGER.log(Level.SEVERE, "Could not close InputStream.", e);
-                }
-            }
+            CloseableUtil.maybeClose(in, LOGGER);
         }
 
         return integers;

smack-openpgp/src/main/java/org/jivesoftware/smackx/ox/store/abstr/AbstractOpenPgpKeyStore.java

@@ -43,7 +43,7 @@ import org.pgpainless.util.BCUtil;
 
 public abstract class AbstractOpenPgpKeyStore implements OpenPgpKeyStore {
 
-    private static final Logger LOGGER = Logger.getLogger(AbstractOpenPgpKeyStore.class.getName());
+    protected static final Logger LOGGER = Logger.getLogger(AbstractOpenPgpKeyStore.class.getName());
 
     protected Map<BareJid, PGPPublicKeyRingCollection> publicKeyRingCollections = new HashMap<>();
     protected Map<BareJid, PGPSecretKeyRingCollection> secretKeyRingCollections = new HashMap<>();

smack-openpgp/src/main/java/org/jivesoftware/smackx/ox/store/filebased/FileBasedOpenPgpKeyStore.java

@@ -27,6 +27,7 @@ import java.io.OutputStream;
 import java.util.Date;
 import java.util.Map;
 
+import org.jivesoftware.smack.util.CloseableUtil;
 import org.jivesoftware.smack.util.Objects;
 import org.jivesoftware.smackx.ox.store.abstr.AbstractOpenPgpKeyStore;
 import org.jivesoftware.smackx.ox.store.definition.OpenPgpKeyStore;
@@ -82,16 +83,8 @@ public class FileBasedOpenPgpKeyStore extends AbstractOpenPgpKeyStore {
         try {
             outputStream = prepareFileOutputStream(file);
             publicKeys.encode(outputStream);
-            outputStream.close();
-        } catch (IOException e) {
-            if (outputStream != null) {
-                try {
-                    outputStream.close();
-                } catch (IOException ignored) {
-                    // Don't care
-                }
-            }
-            throw e;
+        } finally {
+            CloseableUtil.maybeClose(outputStream, LOGGER);
         }
     }
 
@@ -113,16 +106,8 @@ public class FileBasedOpenPgpKeyStore extends AbstractOpenPgpKeyStore {
         try {
             outputStream = prepareFileOutputStream(file);
             secretKeys.encode(outputStream);
-            outputStream.close();
-        } catch (IOException e) {
-            if (outputStream != null) {
-                try {
-                    outputStream.close();
-                } catch (IOException ignored) {
-                    // Don't care
-                }
-            }
-            throw e;
+        } finally {
+            CloseableUtil.maybeClose(outputStream, LOGGER);
         }
     }
 

smack-openpgp/src/main/java/org/jivesoftware/smackx/ox/store/filebased/FileBasedOpenPgpMetadataStore.java

@@ -31,6 +31,7 @@ import java.util.Map;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
+import org.jivesoftware.smack.util.CloseableUtil;
 import org.jivesoftware.smackx.ox.store.abstr.AbstractOpenPgpMetadataStore;
 import org.jivesoftware.smackx.ox.store.definition.OpenPgpMetadataStore;
 import org.jivesoftware.smackx.ox.util.FileUtils;
@@ -110,18 +111,9 @@ public class FileBasedOpenPgpMetadataStore extends AbstractOpenPgpMetadataStore
                 }
             }
 
-            reader.close();
             return fingerprintDateMap;
-
-        } catch (IOException e) {
-            if (reader != null) {
-                try {
-                    reader.close();
-                } catch (IOException ignored) {
-                    // Don't care
-                }
-            }
-            throw e;
+        } finally {
+            CloseableUtil.maybeClose(reader, LOGGER);
         }
     }
 
@@ -166,17 +158,8 @@ public class FileBasedOpenPgpMetadataStore extends AbstractOpenPgpMetadataStore
                 writer.write(line);
                 writer.newLine();
             }
-            writer.flush();
-            writer.close();
-        } catch (IOException e) {
-            if (writer != null) {
-                try {
-                    writer.close();
-                } catch (IOException ignored) {
-                    // Don't care
-                }
-            }
-            throw e;
+        } finally {
+            CloseableUtil.maybeClose(writer, LOGGER);
         }
     }
 
@@ -184,6 +167,7 @@ public class FileBasedOpenPgpMetadataStore extends AbstractOpenPgpMetadataStore
         return new File(FileBasedOpenPgpStore.getContactsPath(basePath, contact), ANNOUNCED);
     }
 
+    // TODO: This method appears to be unused. Remove it?
     private File getRetrievedFingerprintsPath(BareJid contact) {
         return new File(FileBasedOpenPgpStore.getContactsPath(basePath, contact), RETRIEVED);
     }

smack-openpgp/src/main/java/org/jivesoftware/smackx/ox/store/filebased/FileBasedOpenPgpTrustStore.java

@@ -28,6 +28,7 @@ import java.io.OutputStreamWriter;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
+import org.jivesoftware.smack.util.CloseableUtil;
 import org.jivesoftware.smackx.ox.store.abstr.AbstractOpenPgpTrustStore;
 import org.jivesoftware.smackx.ox.store.definition.OpenPgpTrustStore;
 import org.jivesoftware.smackx.ox.util.FileUtils;
@@ -82,21 +83,14 @@ public class FileBasedOpenPgpTrustStore extends AbstractOpenPgpTrustStore {
                             file.getAbsolutePath());
                 }
             }
-            reader.close();
             return trust != null ? trust : Trust.undecided;
         } catch (IOException e) {
-            if (reader != null) {
-                try {
-                    reader.close();
-                } catch (IOException ignored) {
-                    // Don't care
-                }
-            }
-
             if (e instanceof FileNotFoundException) {
                 return Trust.undecided;
             }
             throw e;
+        } finally {
+            CloseableUtil.maybeClose(reader, LOGGER);
         }
     }
 
@@ -134,17 +128,8 @@ public class FileBasedOpenPgpTrustStore extends AbstractOpenPgpTrustStore {
             writer = new BufferedWriter(osw);
 
             writer.write(trust.toString());
-            writer.flush();
-            writer.close();
-        } catch (IOException e) {
-            if (writer != null) {
-                try {
-                    writer.close();
-                } catch (IOException ignored) {
-                    // Don't care
-                }
-            }
-            throw e;
+        } finally {
+            CloseableUtil.maybeClose(writer, LOGGER);
         }
     }
 

smack-resolver-minidns/src/main/java/org/jivesoftware/smack/util/dns/minidns/MiniDnsDaneVerifier.java

@@ -1,6 +1,6 @@
 /**
  *
- * Copyright 2015-2016 Florian Schmaus
+ * Copyright 2015-2018 Florian Schmaus
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,11 +16,9 @@
  */
 package org.jivesoftware.smack.util.dns.minidns;
 
-import java.io.IOException;
 import java.security.KeyManagementException;
 import java.security.SecureRandom;
 import java.security.cert.CertificateException;
-import java.util.logging.Level;
 import java.util.logging.Logger;
 
 import javax.net.ssl.KeyManager;
@@ -29,6 +27,7 @@ import javax.net.ssl.SSLSocket;
 import javax.net.ssl.TrustManager;
 import javax.net.ssl.X509TrustManager;
 
+import org.jivesoftware.smack.util.CloseableUtil;
 import org.jivesoftware.smack.util.dns.SmackDaneVerifier;
 
 import org.minidns.dane.DaneVerifier;
@@ -64,11 +63,7 @@ public class MiniDnsDaneVerifier implements SmackDaneVerifier {
         // DANE verification was successful, but according to the TLSA RR we also must perform PKIX validation.
         if (expectingTrustManager.hasException()) {
             // PKIX validation has failed. Throw an exception but close the socket first.
-            try {
-                sslSocket.close();
-            } catch (IOException e) {
-                LOGGER.log(Level.FINER, "Closing TLS socket failed", e);
-            }
+            CloseableUtil.maybeClose(sslSocket, LOGGER);
             throw expectingTrustManager.getException();
         }
     }

smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java

@@ -125,6 +125,7 @@ import org.jivesoftware.smack.sm.predicates.Predicate;
 import org.jivesoftware.smack.sm.provider.ParseStreamManagement;
 import org.jivesoftware.smack.util.ArrayBlockingQueueWithShutdown;
 import org.jivesoftware.smack.util.Async;
+import org.jivesoftware.smack.util.CloseableUtil;
 import org.jivesoftware.smack.util.DNSUtil;
 import org.jivesoftware.smack.util.PacketParserUtils;
 import org.jivesoftware.smack.util.StringUtils;
@@ -506,11 +507,7 @@ public class XMPPTCPConnection extends AbstractXMPPConnection {
         }
         LOGGER.finer("PacketReader has been shut down");
 
-        try {
-                socket.close();
-        } catch (Exception e) {
-                LOGGER.log(Level.WARNING, "shutdown", e);
-        }
+        CloseableUtil.maybeClose(socket, LOGGER);
 
         setWasAuthenticated();
         // If we are able to resume the stream, then don't set