Use PlainTextWriter for all cli stdout output

src/main/java/org/asamk/signal/commands/GetUserStatusCommand.java

@@ -6,6 +6,7 @@ import net.sourceforge.argparse4j.inf.Subparser;
 
 import org.asamk.signal.JsonWriter;
 import org.asamk.signal.OutputType;
+import org.asamk.signal.PlainTextWriterImpl;
 import org.asamk.signal.manager.Manager;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -69,8 +70,15 @@ public class GetUserStatusCommand implements LocalCommand {
                 return 3;
             }
         } else {
+            final var writer = new PlainTextWriterImpl(System.out);
+
+            try {
                 for (var entry : registered.entrySet()) {
-                System.out.println(entry.getKey() + ": " + entry.getValue());
+                    writer.println("{}: {}", entry.getKey(), entry.getValue());
+                }
+            } catch (IOException e) {
+                e.printStackTrace();
+                return 3;
             }
         }
 

src/main/java/org/asamk/signal/commands/JoinGroupCommand.java

@@ -3,9 +3,12 @@ package org.asamk.signal.commands;
 import net.sourceforge.argparse4j.inf.Namespace;
 import net.sourceforge.argparse4j.inf.Subparser;
 
+import org.asamk.signal.PlainTextWriterImpl;
 import org.asamk.signal.manager.Manager;
 import org.asamk.signal.manager.groups.GroupInviteLinkUrl;
 import org.freedesktop.dbus.exceptions.DBusExecutionException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.whispersystems.signalservice.api.groupsv2.GroupLinkNotActiveException;
 import org.whispersystems.signalservice.internal.push.exceptions.GroupPatchNotAcceptedException;
 
@@ -17,6 +20,8 @@ import static org.asamk.signal.util.ErrorUtils.handleTimestampAndSendMessageResu
 
 public class JoinGroupCommand implements LocalCommand {
 
+    private final static Logger logger = LoggerFactory.getLogger(JoinGroupCommand.class);
+
     @Override
     public void attachToSubparser(final Subparser subparser) {
         subparser.addArgument("--uri").required(true).help("Specify the uri with the group invitation link.");
@@ -42,14 +47,16 @@ public class JoinGroupCommand implements LocalCommand {
         }
 
         try {
+            final var writer = new PlainTextWriterImpl(System.out);
+
             final var results = m.joinGroup(linkUrl);
             var newGroupId = results.first();
             if (!m.getGroup(newGroupId).isMember(m.getSelfAddress())) {
-                System.out.println("Requested to join group \"" + newGroupId.toBase64() + "\"");
+                writer.println("Requested to join group \"{}\"", newGroupId.toBase64());
             } else {
-                System.out.println("Joined group \"" + newGroupId.toBase64() + "\"");
+                writer.println("Joined group \"{}\"", newGroupId.toBase64());
             }
-            return handleTimestampAndSendMessageResults(0, results.second());
+            return handleTimestampAndSendMessageResults(writer, 0, results.second());
         } catch (AssertionError e) {
             handleAssertionError(e);
             return 1;

src/main/java/org/asamk/signal/commands/LinkCommand.java

@@ -3,8 +3,11 @@ package org.asamk.signal.commands;
 import net.sourceforge.argparse4j.inf.Namespace;
 import net.sourceforge.argparse4j.inf.Subparser;
 
+import org.asamk.signal.PlainTextWriterImpl;
 import org.asamk.signal.manager.ProvisioningManager;
 import org.asamk.signal.manager.UserAlreadyExists;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.whispersystems.libsignal.InvalidKeyException;
 
 import java.io.IOException;
@@ -14,6 +17,8 @@ import static org.asamk.signal.util.ErrorUtils.handleAssertionError;
 
 public class LinkCommand implements ProvisioningCommand {
 
+    private final static Logger logger = LoggerFactory.getLogger(LinkCommand.class);
+
     @Override
     public void attachToSubparser(final Subparser subparser) {
         subparser.addArgument("-n", "--name").help("Specify a name to describe this new device.");
@@ -21,14 +26,16 @@ public class LinkCommand implements ProvisioningCommand {
 
     @Override
     public int handleCommand(final Namespace ns, final ProvisioningManager m) {
+        final var writer = new PlainTextWriterImpl(System.out);
+
         var deviceName = ns.getString("name");
         if (deviceName == null) {
             deviceName = "cli";
         }
         try {
-            System.out.println(m.getDeviceLinkUri());
+            writer.println("{}", m.getDeviceLinkUri());
             var username = m.finishDeviceLink(deviceName);
-            System.out.println("Associated with: " + username);
+            writer.println("Associated with: {}", username);
         } catch (TimeoutException e) {
             System.err.println("Link request timed out, please try again.");
             return 3;

src/main/java/org/asamk/signal/commands/ListContactsCommand.java

@@ -3,8 +3,11 @@ package org.asamk.signal.commands;
 import net.sourceforge.argparse4j.inf.Namespace;
 import net.sourceforge.argparse4j.inf.Subparser;
 
+import org.asamk.signal.PlainTextWriterImpl;
 import org.asamk.signal.manager.Manager;
 
+import java.io.IOException;
+
 public class ListContactsCommand implements LocalCommand {
 
     @Override
@@ -13,9 +16,16 @@ public class ListContactsCommand implements LocalCommand {
 
     @Override
     public int handleCommand(final Namespace ns, final Manager m) {
+        final var writer = new PlainTextWriterImpl(System.out);
+
         var contacts = m.getContacts();
+        try {
             for (var c : contacts) {
-            System.out.println(String.format("Number: %s Name: %s  Blocked: %b", c.number, c.name, c.blocked));
+                writer.println("Number: {} Name: {} Blocked: {}", c.number, c.name, c.blocked);
+            }
+        } catch (IOException e) {
+            e.printStackTrace();
+            return 3;
         }
         return 0;
     }

src/main/java/org/asamk/signal/commands/ListDevicesCommand.java

@@ -3,6 +3,7 @@ package org.asamk.signal.commands;
 import net.sourceforge.argparse4j.inf.Namespace;
 import net.sourceforge.argparse4j.inf.Subparser;
 
+import org.asamk.signal.PlainTextWriterImpl;
 import org.asamk.signal.manager.Manager;
 import org.asamk.signal.util.DateUtils;
 
@@ -16,16 +17,16 @@ public class ListDevicesCommand implements LocalCommand {
 
     @Override
     public int handleCommand(final Namespace ns, final Manager m) {
+        final var writer = new PlainTextWriterImpl(System.out);
         try {
             var devices = m.getLinkedDevices();
             for (var d : devices) {
-                System.out.println("Device "
+                writer.println("- Device {}{}:", d.getId(), (d.getId() == m.getDeviceId() ? " (this device)" : ""));
-                        + d.getId()
+                writer.indent(w -> {
-                        + (d.getId() == m.getDeviceId() ? " (this device)" : "")
+                    w.println("Name: {}", d.getName());
-                        + ":");
+                    w.println("Created: {}", DateUtils.formatTimestamp(d.getCreated()));
-                System.out.println(" Name: " + d.getName());
+                    w.println("Last seen: {}", DateUtils.formatTimestamp(d.getLastSeen()));
-                System.out.println(" Created: " + DateUtils.formatTimestamp(d.getCreated()));
+                });
-                System.out.println(" Last seen: " + DateUtils.formatTimestamp(d.getLastSeen()));
             }
             return 0;
         } catch (IOException e) {

src/main/java/org/asamk/signal/commands/ListGroupsCommand.java

@@ -6,6 +6,8 @@ import net.sourceforge.argparse4j.inf.Subparser;
 
 import org.asamk.signal.JsonWriter;
 import org.asamk.signal.OutputType;
+import org.asamk.signal.PlainTextWriter;
+import org.asamk.signal.PlainTextWriterImpl;
 import org.asamk.signal.manager.Manager;
 import org.asamk.signal.manager.storage.groups.GroupInfo;
 import org.slf4j.Logger;
@@ -28,12 +30,14 @@ public class ListGroupsCommand implements LocalCommand {
                 .collect(Collectors.toSet());
     }
 
-    private static void printGroupPlainText(Manager m, GroupInfo group, boolean detailed) {
+    private static void printGroupPlainText(
+            PlainTextWriter writer, Manager m, GroupInfo group, boolean detailed
+    ) throws IOException {
         if (detailed) {
             final var groupInviteLink = group.getGroupInviteLink();
 
-            System.out.println(String.format(
+            writer.println(
-                    "Id: %s Name: %s  Active: %s Blocked: %b Members: %s Pending members: %s Requesting members: %s Link: %s",
+                    "Id: {} Name: {}  Active: {} Blocked: {} Members: {} Pending members: {} Requesting members: {} Link: {}",
                     group.getGroupId().toBase64(),
                     group.getTitle(),
                     group.isMember(m.getSelfAddress()),
@@ -41,13 +45,13 @@ public class ListGroupsCommand implements LocalCommand {
                     resolveMembers(m, group.getMembers()),
                     resolveMembers(m, group.getPendingMembers()),
                     resolveMembers(m, group.getRequestingMembers()),
-                    groupInviteLink == null ? '-' : groupInviteLink.getUrl()));
+                    groupInviteLink == null ? '-' : groupInviteLink.getUrl());
         } else {
-            System.out.println(String.format("Id: %s Name: %s  Active: %s Blocked: %b",
+            writer.println("Id: {} Name: {}  Active: {} Blocked: {}",
                     group.getGroupId().toBase64(),
                     group.getTitle(),
                     group.isMember(m.getSelfAddress()),
-                    group.isBlocked()));
+                    group.isBlocked());
         }
     }
 
@@ -93,9 +97,15 @@ public class ListGroupsCommand implements LocalCommand {
 
             return 0;
         } else {
+            final var writer = new PlainTextWriterImpl(System.out);
             boolean detailed = ns.getBoolean("detailed");
+            try {
                 for (var group : m.getGroups()) {
-                printGroupPlainText(m, group, detailed);
+                    printGroupPlainText(writer, m, group, detailed);
+                }
+            } catch (IOException e) {
+                e.printStackTrace();
+                return 3;
             }
         }
 

src/main/java/org/asamk/signal/commands/ListIdentitiesCommand.java

@@ -3,22 +3,34 @@ package org.asamk.signal.commands;
 import net.sourceforge.argparse4j.inf.Namespace;
 import net.sourceforge.argparse4j.inf.Subparser;
 
+import org.asamk.signal.PlainTextWriter;
+import org.asamk.signal.PlainTextWriterImpl;
 import org.asamk.signal.manager.Manager;
 import org.asamk.signal.manager.storage.protocol.IdentityInfo;
 import org.asamk.signal.util.Hex;
 import org.asamk.signal.util.Util;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.whispersystems.signalservice.api.util.InvalidNumberException;
 
+import java.io.IOException;
+
 public class ListIdentitiesCommand implements LocalCommand {
 
-    private static void printIdentityFingerprint(Manager m, IdentityInfo theirId) {
+    private final static Logger logger = LoggerFactory.getLogger(ListIdentitiesCommand.class);
+
+    private static void printIdentityFingerprint(PlainTextWriter writer, Manager m, IdentityInfo theirId) {
         var digits = Util.formatSafetyNumber(m.computeSafetyNumber(theirId.getAddress(), theirId.getIdentityKey()));
-        System.out.println(String.format("%s: %s Added: %s Fingerprint: %s Safety Number: %s",
+        try {
+            writer.println("{}: {} Added: {} Fingerprint: {} Safety Number: {}",
                     theirId.getAddress().getNumber().orNull(),
                     theirId.getTrustLevel(),
                     theirId.getDateAdded(),
                     Hex.toString(theirId.getFingerprint()),
-                digits));
+                    digits);
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
     }
 
     @Override
@@ -28,16 +40,18 @@ public class ListIdentitiesCommand implements LocalCommand {
 
     @Override
     public int handleCommand(final Namespace ns, final Manager m) {
+        final var writer = new PlainTextWriterImpl(System.out);
+
         if (ns.get("number") == null) {
             for (var identity : m.getIdentities()) {
-                printIdentityFingerprint(m, identity);
+                printIdentityFingerprint(writer, m, identity);
             }
         } else {
             var number = ns.getString("number");
             try {
                 var identities = m.getIdentities(number);
                 for (var id : identities) {
-                    printIdentityFingerprint(m, id);
+                    printIdentityFingerprint(writer, m, id);
                 }
             } catch (InvalidNumberException e) {
                 System.err.println("Invalid number: " + e.getMessage());

src/main/java/org/asamk/signal/commands/QuitGroupCommand.java

@@ -3,6 +3,7 @@ package org.asamk.signal.commands;
 import net.sourceforge.argparse4j.inf.Namespace;
 import net.sourceforge.argparse4j.inf.Subparser;
 
+import org.asamk.signal.PlainTextWriterImpl;
 import org.asamk.signal.manager.Manager;
 import org.asamk.signal.manager.groups.GroupIdFormatException;
 import org.asamk.signal.manager.groups.GroupNotFoundException;
@@ -28,9 +29,11 @@ public class QuitGroupCommand implements LocalCommand {
     @Override
     public int handleCommand(final Namespace ns, final Manager m) {
         try {
+            final var writer = new PlainTextWriterImpl(System.out);
+
             final var groupId = Util.decodeGroupId(ns.getString("group"));
             final var results = m.sendQuitGroupMessage(groupId);
-            return handleTimestampAndSendMessageResults(results.first(), results.second());
+            return handleTimestampAndSendMessageResults(writer, results.first(), results.second());
         } catch (IOException e) {
             handleIOException(e);
             return 3;

src/main/java/org/asamk/signal/commands/ReceiveCommand.java

@@ -8,6 +8,7 @@ import org.asamk.Signal;
 import org.asamk.signal.JsonReceiveMessageHandler;
 import org.asamk.signal.JsonWriter;
 import org.asamk.signal.OutputType;
+import org.asamk.signal.PlainTextWriterImpl;
 import org.asamk.signal.ReceiveMessageHandler;
 import org.asamk.signal.json.JsonMessageEnvelope;
 import org.asamk.signal.manager.Manager;
@@ -55,10 +56,11 @@ public class ReceiveCommand implements ExtendedDbusCommand, LocalCommand {
             logger.warn("\"--json\" option has been deprecated, please use the global \"--output=json\" instead.");
         }
 
-        final var jsonWriter = inJson ? new JsonWriter(System.out) : null;
         try {
+            if (inJson) {
+                final var jsonWriter = new JsonWriter(System.out);
+
                 dbusconnection.addSigHandler(Signal.MessageReceived.class, messageReceived -> {
-                if (jsonWriter != null) {
                     var envelope = new JsonMessageEnvelope(messageReceived);
                     final var object = Map.of("envelope", envelope);
                     try {
@@ -66,27 +68,9 @@ public class ReceiveCommand implements ExtendedDbusCommand, LocalCommand {
                     } catch (IOException e) {
                         logger.error("Failed to write json object: {}", e.getMessage());
                     }
-                } else {
-                    System.out.print(String.format("Envelope from: %s\nTimestamp: %s\nBody: %s\n",
-                            messageReceived.getSender(),
-                            DateUtils.formatTimestamp(messageReceived.getTimestamp()),
-                            messageReceived.getMessage()));
-                    if (messageReceived.getGroupId().length > 0) {
-                        System.out.println("Group info:");
-                        System.out.println("  Id: " + Base64.getEncoder().encodeToString(messageReceived.getGroupId()));
-                    }
-                    if (messageReceived.getAttachments().size() > 0) {
-                        System.out.println("Attachments: ");
-                        for (var attachment : messageReceived.getAttachments()) {
-                            System.out.println("-  Stored plaintext in: " + attachment);
-                        }
-                    }
-                    System.out.println();
-                }
                 });
 
                 dbusconnection.addSigHandler(Signal.ReceiptReceived.class, receiptReceived -> {
-                if (jsonWriter != null) {
                     var envelope = new JsonMessageEnvelope(receiptReceived);
                     final var object = Map.of("envelope", envelope);
                     try {
@@ -94,15 +78,9 @@ public class ReceiveCommand implements ExtendedDbusCommand, LocalCommand {
                     } catch (IOException e) {
                         logger.error("Failed to write json object: {}", e.getMessage());
                     }
-                } else {
-                    System.out.print(String.format("Receipt from: %s\nTimestamp: %s\n",
-                            receiptReceived.getSender(),
-                            DateUtils.formatTimestamp(receiptReceived.getTimestamp())));
-                }
                 });
 
                 dbusconnection.addSigHandler(Signal.SyncMessageReceived.class, syncReceived -> {
-                if (jsonWriter != null) {
                     var envelope = new JsonMessageEnvelope(syncReceived);
                     final var object = Map.of("envelope", envelope);
                     try {
@@ -110,25 +88,66 @@ public class ReceiveCommand implements ExtendedDbusCommand, LocalCommand {
                     } catch (IOException e) {
                         logger.error("Failed to write json object: {}", e.getMessage());
                     }
+                });
             } else {
-                    System.out.print(String.format("Sync Envelope from: %s to: %s\nTimestamp: %s\nBody: %s\n",
+                final var writer = new PlainTextWriterImpl(System.out);
-                            syncReceived.getSource(),
+
-                            syncReceived.getDestination(),
+                dbusconnection.addSigHandler(Signal.MessageReceived.class, messageReceived -> {
-                            DateUtils.formatTimestamp(syncReceived.getTimestamp()),
+                    try {
-                            syncReceived.getMessage()));
+                        writer.println("Envelope from: {}", messageReceived.getSender());
-                    if (syncReceived.getGroupId().length > 0) {
+                        writer.println("Timestamp: {}", DateUtils.formatTimestamp(messageReceived.getTimestamp()));
-                        System.out.println("Group info:");
+                        writer.println("Body: {}", messageReceived.getMessage());
-                        System.out.println("  Id: " + Base64.getEncoder().encodeToString(syncReceived.getGroupId()));
+                        if (messageReceived.getGroupId().length > 0) {
+                            writer.println("Group info:");
+                            writer.indentedWriter()
+                                    .println("Id: {}",
+                                            Base64.getEncoder().encodeToString(messageReceived.getGroupId()));
                         }
-                    if (syncReceived.getAttachments().size() > 0) {
+                        if (messageReceived.getAttachments().size() > 0) {
-                        System.out.println("Attachments: ");
+                            writer.println("Attachments:");
-                        for (var attachment : syncReceived.getAttachments()) {
+                            for (var attachment : messageReceived.getAttachments()) {
-                            System.out.println("-  Stored plaintext in: " + attachment);
+                                writer.println("- Stored plaintext in: {}", attachment);
                             }
                         }
-                    System.out.println();
+                        writer.println();
+                    } catch (IOException e) {
+                        e.printStackTrace();
                     }
                 });
+
+                dbusconnection.addSigHandler(Signal.ReceiptReceived.class, receiptReceived -> {
+                    try {
+                        writer.println("Receipt from: {}", receiptReceived.getSender());
+                        writer.println("Timestamp: {}", DateUtils.formatTimestamp(receiptReceived.getTimestamp()));
+                    } catch (IOException e) {
+                        e.printStackTrace();
+                    }
+                });
+
+                dbusconnection.addSigHandler(Signal.SyncMessageReceived.class, syncReceived -> {
+                    try {
+                        writer.println("Sync Envelope from: {} to: {}",
+                                syncReceived.getSource(),
+                                syncReceived.getDestination());
+                        writer.println("Timestamp: {}", DateUtils.formatTimestamp(syncReceived.getTimestamp()));
+                        writer.println("Body: {}", syncReceived.getMessage());
+                        if (syncReceived.getGroupId().length > 0) {
+                            writer.println("Group info:");
+                            writer.indentedWriter()
+                                    .println("Id: {}", Base64.getEncoder().encodeToString(syncReceived.getGroupId()));
+                        }
+                        if (syncReceived.getAttachments().size() > 0) {
+                            writer.println("Attachments:");
+                            for (var attachment : syncReceived.getAttachments()) {
+                                writer.println("- Stored plaintext in: {}", attachment);
+                            }
+                        }
+                        writer.println();
+                    } catch (IOException e) {
+                        e.printStackTrace();
+                    }
+                });
+            }
         } catch (DBusException e) {
             e.printStackTrace();
             return 2;

src/main/java/org/asamk/signal/commands/SendCommand.java

@@ -5,11 +5,14 @@ import net.sourceforge.argparse4j.inf.Namespace;
 import net.sourceforge.argparse4j.inf.Subparser;
 
 import org.asamk.Signal;
+import org.asamk.signal.PlainTextWriterImpl;
 import org.asamk.signal.manager.groups.GroupIdFormatException;
 import org.asamk.signal.util.IOUtils;
 import org.asamk.signal.util.Util;
 import org.freedesktop.dbus.errors.UnknownObject;
 import org.freedesktop.dbus.exceptions.DBusExecutionException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
 import java.nio.charset.Charset;
@@ -20,6 +23,8 @@ import static org.asamk.signal.util.ErrorUtils.handleGroupIdFormatException;
 
 public class SendCommand implements DbusCommand {
 
+    private final static Logger logger = LoggerFactory.getLogger(SendCommand.class);
+
     @Override
     public void attachToSubparser(final Subparser subparser) {
         subparser.addArgument("recipient").help("Specify the recipients' phone number.").nargs("*");
@@ -90,8 +95,9 @@ public class SendCommand implements DbusCommand {
             attachments = List.of();
         }
 
+        final var writer = new PlainTextWriterImpl(System.out);
+
         if (groupIdString != null) {
-            try {
             byte[] groupId;
             try {
                 groupId = Util.decodeGroupId(groupIdString).serialize();
@@ -100,8 +106,9 @@ public class SendCommand implements DbusCommand {
                 return 1;
             }
 
+            try {
                 var timestamp = signal.sendGroupMessage(messageText, attachments, groupId);
-                System.out.println(timestamp);
+                writer.println("{}", timestamp);
                 return 0;
             } catch (AssertionError e) {
                 handleAssertionError(e);
@@ -109,13 +116,16 @@ public class SendCommand implements DbusCommand {
             } catch (DBusExecutionException e) {
                 System.err.println("Failed to send group message: " + e.getMessage());
                 return 2;
+            } catch (IOException e) {
+                e.printStackTrace();
+                return 3;
             }
         }
 
         if (isNoteToSelf) {
             try {
                 var timestamp = signal.sendNoteToSelfMessage(messageText, attachments);
-                System.out.println(timestamp);
+                writer.println("{}", timestamp);
                 return 0;
             } catch (AssertionError e) {
                 handleAssertionError(e);
@@ -126,12 +136,15 @@ public class SendCommand implements DbusCommand {
             } catch (DBusExecutionException e) {
                 System.err.println("Failed to send note to self message: " + e.getMessage());
                 return 2;
+            } catch (IOException e) {
+                e.printStackTrace();
+                return 3;
             }
         }
 
         try {
             var timestamp = signal.sendMessage(messageText, attachments, recipients);
-            System.out.println(timestamp);
+            writer.println("{}", timestamp);
             return 0;
         } catch (AssertionError e) {
             handleAssertionError(e);
@@ -145,6 +158,9 @@ public class SendCommand implements DbusCommand {
         } catch (DBusExecutionException e) {
             System.err.println("Failed to send message: " + e.getMessage());
             return 2;
+        } catch (IOException e) {
+            e.printStackTrace();
+            return 3;
         }
     }
 }

src/main/java/org/asamk/signal/commands/SendReactionCommand.java

@@ -4,6 +4,7 @@ import net.sourceforge.argparse4j.impl.Arguments;
 import net.sourceforge.argparse4j.inf.Namespace;
 import net.sourceforge.argparse4j.inf.Subparser;
 
+import org.asamk.signal.PlainTextWriterImpl;
 import org.asamk.signal.manager.Manager;
 import org.asamk.signal.manager.groups.GroupIdFormatException;
 import org.asamk.signal.manager.groups.GroupNotFoundException;
@@ -66,6 +67,8 @@ public class SendReactionCommand implements LocalCommand {
         final long targetTimestamp = ns.getLong("target_timestamp");
 
         try {
+            final var writer = new PlainTextWriterImpl(System.out);
+
             final Pair<Long, List<SendMessageResult>> results;
             if (groupIdString != null) {
                 var groupId = Util.decodeGroupId(groupIdString);
@@ -73,7 +76,7 @@ public class SendReactionCommand implements LocalCommand {
             } else {
                 results = m.sendMessageReaction(emoji, isRemove, targetAuthor, targetTimestamp, recipients);
             }
-            return handleTimestampAndSendMessageResults(results.first(), results.second());
+            return handleTimestampAndSendMessageResults(writer, results.first(), results.second());
         } catch (IOException e) {
             handleIOException(e);
             return 3;

src/main/java/org/asamk/signal/commands/UpdateGroupCommand.java

@@ -4,10 +4,14 @@ import net.sourceforge.argparse4j.inf.Namespace;
 import net.sourceforge.argparse4j.inf.Subparser;
 
 import org.asamk.Signal;
+import org.asamk.signal.PlainTextWriterImpl;
 import org.asamk.signal.manager.groups.GroupIdFormatException;
 import org.asamk.signal.util.Util;
 import org.freedesktop.dbus.exceptions.DBusExecutionException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
+import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Base64;
 import java.util.List;
@@ -17,6 +21,8 @@ import static org.asamk.signal.util.ErrorUtils.handleGroupIdFormatException;
 
 public class UpdateGroupCommand implements DbusCommand {
 
+    private final static Logger logger = LoggerFactory.getLogger(UpdateGroupCommand.class);
+
     @Override
     public void attachToSubparser(final Subparser subparser) {
         subparser.addArgument("-g", "--group").help("Specify the recipient group ID.");
@@ -27,6 +33,7 @@ public class UpdateGroupCommand implements DbusCommand {
 
     @Override
     public int handleCommand(final Namespace ns, final Signal signal) {
+        final var writer = new PlainTextWriterImpl(System.out);
         byte[] groupId = null;
         if (ns.getString("group") != null) {
             try {
@@ -58,7 +65,12 @@ public class UpdateGroupCommand implements DbusCommand {
         try {
             var newGroupId = signal.updateGroup(groupId, groupName, groupMembers, groupAvatar);
             if (groupId.length != newGroupId.length) {
-                System.out.println("Creating new group \"" + Base64.getEncoder().encodeToString(newGroupId) + "\" …");
+                try {
+                    writer.println("Creating new group \"{}\" …", Base64.getEncoder().encodeToString(newGroupId));
+                } catch (IOException e) {
+                    e.printStackTrace();
+                    return 3;
+                }
             }
             return 0;
         } catch (AssertionError e) {

src/main/java/org/asamk/signal/commands/UploadStickerPackCommand.java

@@ -3,14 +3,19 @@ package org.asamk.signal.commands;
 import net.sourceforge.argparse4j.inf.Namespace;
 import net.sourceforge.argparse4j.inf.Subparser;
 
+import org.asamk.signal.PlainTextWriterImpl;
 import org.asamk.signal.manager.Manager;
 import org.asamk.signal.manager.StickerPackInvalidException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.io.File;
 import java.io.IOException;
 
 public class UploadStickerPackCommand implements LocalCommand {
 
+    private final static Logger logger = LoggerFactory.getLogger(UploadStickerPackCommand.class);
+
     @Override
     public void attachToSubparser(final Subparser subparser) {
         subparser.addArgument("path")
@@ -19,10 +24,11 @@ public class UploadStickerPackCommand implements LocalCommand {
 
     @Override
     public int handleCommand(final Namespace ns, final Manager m) {
+        final var writer = new PlainTextWriterImpl(System.out);
         try {
             var path = new File(ns.getString("path"));
             var url = m.uploadStickerPack(path);
-            System.out.println(url);
+            writer.println("{}", url);
             return 0;
         } catch (IOException e) {
             System.err.println("Upload error: " + e.getMessage());

src/main/java/org/asamk/signal/util/ErrorUtils.java

@@ -1,5 +1,6 @@
 package org.asamk.signal.util;
 
+import org.asamk.signal.PlainTextWriter;
 import org.asamk.signal.manager.groups.GroupIdFormatException;
 import org.asamk.signal.manager.groups.GroupNotFoundException;
 import org.asamk.signal.manager.groups.NotAGroupMemberException;
@@ -22,9 +23,13 @@ public class ErrorUtils {
                 "If you use an Oracle JRE please check if you have unlimited strength crypto enabled, see README");
     }
 
-    public static int handleTimestampAndSendMessageResults(long timestamp, List<SendMessageResult> results) {
+    public static int handleTimestampAndSendMessageResults(
+            PlainTextWriter writer,
+            long timestamp,
+            List<SendMessageResult> results
+    ) throws IOException {
         if (timestamp != 0) {
-            System.out.println(timestamp);
+            writer.println("{}", timestamp);
         }
         var errors = getErrorMessagesFromSendMessageResults(results);
         return handleSendMessageResultErrors(errors);