Android java set environment variable

How do I set environment variables from Java?

To a system property from Java, you can use the System.setProperty() method. However, keep in mind that this method only sets system properties, which are different from environment variables.

System properties are a set of key-value pairs that can be set at the Java Virtual Machine (JVM) level, and are used to configure the behavior of the JVM and Java applications. They are stored in the java.lang.System class, and can be accessed using the System.getProperty() method.

To set a system property from Java, you can use the System.setProperty() method, like this:

System.setProperty("propertyName", "propertyValue");

System.setProperty("java.io.tmpdir", "/tmp");

This will set the java.io.tmpdir system property to the value «/tmp» .

Environment variables, on the other hand, are system-wide variables that are set outside of the JVM and are used to configure the operating system and other programs. They can be accessed using the System.getenv() method.

To set an environment variable from Java, you will need to use a native method or a third-party library that allows you to set environment variables.

One way to set environment variables from Java is to use the ProcessBuilder class. The ProcessBuilder class allows you to start a new process with a modified environment, which inherits the current process’s environment and allows you to make changes to it. Here’s an example of how you can set an environment variable using ProcessBuilder:

import java.io.IOException; import java.util.Map; public class SetEnvironmentVariable < public static void main(String[] args) < try < // Create a new ProcessBuilder instance ProcessBuilder processBuilder = new ProcessBuilder(); // Get the environment variables from the ProcessBuilder instance Map environment = processBuilder.environment(); // Set a new environment variable environment.put("MY_ENV_VAR", "MyEnvironmentVariableValue"); // Run a command with the modified environment processBuilder.command("someCommand"); Process process = processBuilder.start(); process.waitFor(); > catch (IOException | InterruptedException e) < e.printStackTrace(); >> >

In this example, we first create a new ProcessBuilder instance. Then, we retrieve the environment variables from the ProcessBuilder by calling the environment() method. Next, we set a new environment variable by calling the put() method on the Map of environment variables. Finally, we run a command using the start() method, which launches a new process with the modified environment.

Please note that this approach sets the environment variable for the new process and its child processes, but not for the current JVM process. The new environment variable will not be accessible from the current JVM process using System.getenv() .

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Code example for setting Android home environment variable in Java

While setting an environment variable from the adb shell, it should be noted that the variable cannot be accessed by the Android application as it is not in the parent process of the launching process. However, there is an alternative solution where environment variables can be set within the Android application itself.

Android set(get) environmental variables in Java

An environment variable is only accessible to the process that sets it and any child processes created after that. If you set an environment variable from adb shell, it won’t be visible to the parent process that launches the Android application, which means the application won’t be able to access the variable you set.

Java (including Android) does not support System.setenv() for setting environment variables. However, if you require an environment variable for your program to access, there are alternative methods that are more effective. One such method involves utilizing Properties to set and retrieve values.

Java does not provide an easy way to set a variable for another process to read. However, if the process is launched from a Java/Android program, you can utilize ProcessBuilder to achieve this functionality.

Consider the issue you aim to resolve and explore alternative solutions that do not involve the use of environment variables. In Java, environment variables may not be the optimal choice, and their use can be particularly problematic on Android.

As per @richq’s statement, set environment variables can be included in Android applications, but it will be restricted to processes launched from the same application that contains set environment variable and the JNI libraries used by it. Refer to this post on Stack Overflow for guidance on setting environment variables in Android applications: https://stackoverflow.com/a/22315463/927592.

Android API 21 offers a method for configuring environment variables, which involves executing Os.setenv .

Refer to both the android.system.Os documentation and the setenv(3) documentation.

The environment of each process is derived from its parent process and is unique to that process, making environment variables specific to each process.

Is it possible to set an environment variable at runtime, This works on java 1.8.0_144. Can’t guarantee it works on any other version of java, but it’s probably similar if you really need to change the environment at run time. private static Map getModifiableEnvironment () throws Exception < Class pe = Class.forName ("java.lang.ProcessEnvironment"); Method getenv = …

How to set and use an environment variable in Android Test?

The environment variable’s visibility is restricted to the processes that originate from or are identical to the one that initializes the variable’s value. (refer to http://en.wikipedia.org/wiki/Environment_variable#Synopsis for more information)

Your difficulty in perceiving the worth you establish can be attributed to the circumstance where the process used to retrieve the value is not a successor of the process used to assign it.

To determine the appropriate location for setting the value, it’s important to analyze the process hierarchy of your application(s).

The following approach can be used to both retrieve and update a property.

System.getProperty('property_name'); System.setProperty('property_name', 'value'); 

The method System.getenv() can be used to retrieve a collection of all the environment variables that are currently available.

In case it is still not working, could you share some of your code?

If you have experience with utilizing the NDK, you can either incorporate the line into an already existing function or generate a native function within the NDK space.

setenv("ENVIROMENT_VARIABLE", "value", 1); 

Utilizing the java APIs System.getenv() can enable you to retrieve the stored information.

Although it may be inconvenient, it is essential to utilize online code analysis tools such as gcov (which is provided with the android ndk) to achieve code coverage.

Set ANDROID_HOME in Environment Variable Code, Get code examples like «set ANDROID_HOME in Environment Variable» instantly right from your google search results with …

Can I set environment variables from code? [duplicate]

import java.io.*; import java.util.*; public class Test < public static void main(String[] args) throws Exception < ProcessBuilder pb = new ProcessBuilder("CMD.exe", "/C", "SET"); // SET prints out the environment variables pb.redirectErrorStream(true); Mapenv = pb.environment(); String path = env.get("Path") + ";C:\\naved\\bin"; env.put("Path", path); Process process = pb.start(); BufferedReader in = new BufferedReader(new InputStreamReader(process.getInputStream())); String line; while ((line = in.readLine()) != null) < System.out.println(line); >> > 

Java — Can I set environment variables from code?, There arises a need to set environment variable’s , how can I set environment variable? I tried using ProcessBuilder but it doesn’t work: ProcessBuilder pb = Stack Overflow. About; Products For Teams; Stack Overflow Public questions & answers; Stack Overflow for Teams Where developers & …

Android — Environment Setup

You have the option to initiate your Android application development on any of these operating systems —

• Microsoft operating systems from XP onwards.
• A computer with an Intel chip must have a version of Mac OS X that is 10.5.8 or later.
• Linux operating system that comes with GNU C Library version 2.7 or above.

The next important aspect to consider is that the essential resources for creating Android apps can be obtained at no cost via online sources. Here are the software components that you should acquire prior to commencing your Android application development.

• Java JDK5 or later version

• Android Studio

The last two components are not mandatory, but if you are developing a Java-based application on a Windows machine, they can simplify your work. Let’s explore the steps to set up the necessary environment.

Set-up Java Development Kit (JDK)

Visit Oracle’s Java SE Downloads website to get the most recent version of Java JDK. The downloaded files will provide guidance on how to install and set up the JDK. To ensure that the directory containing «java» and «javac» (usually java_install_dir/bin and java_install_dir, respectively) is referenced correctly, make sure to set the PATH and JAVA_HOME environment variables.

To incorporate the JDK in C:\jdk1.8.0_102 on a Windows operating system, it is necessary to add a line to the C:\autoexec.bat file.

set PATH=C:\jdk1.8.0_102\bin;%PATH% set JAVA_HOME=C:\jdk1.8.0_102

Another option is to access the Environment Variables settings. To do this, you can right-click on My Computer and choose Properties. From there, select Advanced and navigate to Environment Variables. Once there, you can modify the PATH value as needed and click OK to save the changes.

If you are a Linux user and have installed the SDK at /usr/local/jdk1.8.0_102, you can add the given code to your .cshrc file if you use the C shell.

setenv PATH /usr/local/jdk1.8.0_102/bin:$PATH setenv JAVA_HOME /usr/local/jdk1.8.0_102

In case you utilize Android studio, it will automatically detect the location of your Java installation.

Android IDEs

A multitude of advanced technologies exist for creating Android applications. These include several well-known tools commonly utilized.

• Android Studio

• Eclipse IDE(Deprecated)

Android — How can i set the environment variable, I was using this example . But while i run my code i got following exception Failed to . Stack Overflow. About ; Products For Teams; Stack Overflow Public questions & answers; Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Talent Build your …

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Android set(get) environmental variables in Java

Environment variables are only visible in a process that sets the variable, and child processes launched after setting the variable. When you set the environment variable from the adb shell you are not in the parent process of the process that launches the Android application, so the application cannot see the variable you set.

In Java (and Android) there is no System.setenv() , but if you need to set an environment variable for your own program to read there are always better ways. One such way is setting and getting Properties instead.

Setting environment variables in Java is not really possible (well, it is, but you don’t want to do it). You can use ProcessBuilder if you want to set a variable that another process should read, but that’s if the process is launched from a Java/Android program.

Think about what problem you’re trying to solve, and if it can be done without using environment variables. They’re not a good fit in Java, and are even worse on Android.

It is possible to set environment variables in Android applications. However, as @richq said, those variables will be only visible in processes launched from the application that has set environment variable (and JNI libraries used by the application). See this post for regarding setting environment variables from Android application: https://stackoverflow.com/a/22315463/927592

Android API 21 provides a way to set the environment variables. To set an environment variable, invoke Os.setenv .

See this android.system.Os documentation and this setenv(3) documentation.

Each process has its own environment, which is copied from the parent process’s environment. So the environment variables are per-process.

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