Android NetTool

Building

Getting libraries and SDKs

Create "libs" dir

mkdir libs

• Get JDK from Oracle's website, tar.gz version will work fine
• Get Android SDK (stand-alone Android SDK Tools)
• Get Android NDK
• Get AndroidPlot library's JAR file from it's site, put it into project's "libs" directory

Unpack JDK and Android SDK/NDK Copy paths to root JDK directory, Android SDK's "tools" directory and android NDK's directory into android_paths script, it should look something like that:

export JAVA_HOME="/home/user/Dev/jdk1.8.0_31"
export NDK_HOME="/home/user/Dev/android-ndk-r10d"
export ANDROID_HOME="/home/user/Dev/android-sdk_r24.0.2-linux/android-sdk-linux/tools"

Update PATH variable before working with Android SDK calling this command:

source android_paths

Android SDK Manager

To launch Android SDK Manager run command:

android &

Click there "Deselect All" to skip unwanted packages for now. Select and install "Extras / Android Support Library".

Copy Android support library into project's directory

cp $ANDROID_HOME/../extras/android/support/v4/android-support-v4.jar libs/

From Android 5.0.1 (API 21) install

• SDK Platform
• To work with emulator - Intel x86 Atom System Image
• Another Android SDK Platforms if required

Install "Tools / Android SDK Build-tools 21.1.2"

You'll need to update "PATH" variable in android_paths script to use another version of Build-tools

Close SDK Manager

List available targets

android list target

Note the ID for target (default: Android 5.0.1)

Prepare project for building

android update project -t <id> -p .

Building

Builds can be found in "bin" directory

Debug version

./build_debug

Release version

Generate keystore with release signing key in it

Make sure you're not overwriting existing keystore file (NetTool-release.keystore in current directory)

Run the command:

$JAVA_HOME/bin/keytool -genkey -v -keystore NetTool-release.keystore -alias NetTool-key -keyalg RSA -keysize 2048 -validity 10000

1. Enter password for keystore. You'll need it to access keys stored in it.
2. Enter information for key.
3. Enter password for key.

NOTE: If you plan to publish the app on Google Play, you'd like to keep your release signing key to update the app in the future. It's impossible to update the app with different key.

More information at Signing Your App Manually

Build, sign and zipalign APK

./build_release <path to keystore>

During building, at signing stage, you'll be asked for keystore password and key password (if it's different from keystore's password)

NetTool-release.apk is located in "bin" directory.

Emulator

To create virtual devices for emulator run next command:

android avd

After creating device, note it's name and from root project directory run command:

./run_emulator <avd name> [scale]

Installing APK onto device or emulator using adb

To list available devices run command

adb devices

To install APK onto one of the listed devices run

adb -s <device name> install -r <apk path>

Sending datagrams with configuration messages

Datagrams can be sent to all devices connected to the network using auxiliary scripts located in "datagram_utils" directory. The directory contains:

• broadcast_series.sh
• broadcast_to_peds.sh
• datagram_test.conf

Configuration message file and datagram_test.conf

The configuration message is contained in text file. The example of such message can be found in "datagram_text.conf" file. Every available option is listed there and prepended with description. Lines can be commented out using "#" (number sign, hash) symbol.

Script broadcast_to_peds.sh

broadcast_to_peds.sh is the script which actually sends the configuration file using "socat", what implies that "socat" has to be installed on the system where the script is used. Configuration file path is specified in first argument. Before sending commented and empty lines of the message will be removed using "sed". Also, the message will be prepended with "message_id" option (which is taken from second argument and defaults to "-1" if not provided). After that the message is UDP broadcasted using "socat" on "255.255.255.255:55555" address and port.

broadcast_to_peds.sh filepath [message id]

Script broadcast_series.sh

Because the UDP datagram may be missed by the device for various reasons, there exists another auxiliary script - broadcast_series.sh.

The purpose of this script is sending one single message repeatedly for specified number of times and with specified delay. Default number of repeats is 5 and default delay is 200 ms.

This script calls broadcast_to_peds.sh and provides message id to it. The message id in this case is result of running date +%s command. Each message from the sequence has same message id. The app, before processing received message, checks the id and discards the message if it was processed before.

broadcast_series.sh filepath [number of repeats] [delay]

It's recommended to use broadcast_series.sh script for sending messages.