Adding the ability to enable tcpip from the library as per https://github.com/aosp-mirror/platform_system_core/blob/master/adb/daemon/services.cpp

src/se/vidstige/jadb/JadbDevice.java

@@ -1,11 +1,13 @@
 package se.vidstige.jadb;
 
 import se.vidstige.jadb.managers.Bash;
-
 import java.io.*;
+import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.List;
 
+import static se.vidstige.jadb.Util.inputStreamToString;
+
 public class JadbDevice {
     @SuppressWarnings("squid:S00115")
     public enum State {
@@ -146,10 +148,7 @@ public class JadbDevice {
      * @return success or failure
      */
     public boolean enableTcpip() throws IOException, JadbException {
-        Transport transport = getTransport();
-
-        send(transport, String.format("tcpip: %d", DEFAULT_TCPIP_PORT));
-        return transport.readString().trim().equals(String.format("restarting in TCP Mode: %d", DEFAULT_TCPIP_PORT));
+        return enableTcpip(DEFAULT_TCPIP_PORT);
     }
 
     /**
@@ -161,8 +160,10 @@ public class JadbDevice {
      */
     public boolean enableTcpip(int port) throws IOException, JadbException {
         Transport transport = getTransport();
-        send(transport, String.format("tcpip: %d", port));
-        return transport.readString().trim().equals(String.format("restarting in TCP Mode: %d", port));
+        send(transport, String.format("tcpip:%d", port));
+        String expectedResult = String.format("restarting in TCP Mode: %d", port);
+
+        return inputStreamToString(transport.getInputStream()).equals(expectedResult);
     }
 
     public List<RemoteFile> list(String remotePath) throws IOException, JadbException {

src/se/vidstige/jadb/Util.java

@@ -0,0 +1,28 @@
+package se.vidstige.jadb;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
+
+public class Util {
+    /**
+     * Convert an input stream to string
+     *
+     * @param inputStream input stream
+     *
+     * @return string representation of the input stream
+     *
+     * @throws IOException if an error ocurrs reading the input stream
+     */
+    public static String inputStreamToString(InputStream inputStream) throws IOException {
+        ByteArrayOutputStream result = new ByteArrayOutputStream();
+        byte[] buffer = new byte[1024];
+        int length;
+        while ((length = inputStream.read(buffer)) != -1) {
+            result.write(buffer, 0, length);
+        }
+
+        return result.toString(StandardCharsets.UTF_8.name());
+    }
+}