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code snippets we love @ Universal Equations: Setting Environment Variables Programmatically (Java)

code snippets we love @ Universal Equations(https://www.uequations.com):

Setting Environment Variables Programmatically (Java)

public static void setEnv(Map<String, String> newenv)
{
try
{
Class<?> processEnvironmentClass = Class.forName("java.lang.ProcessEnvironment");
Field theEnvironmentField = processEnvironmentClass.getDeclaredField("theEnvironment");
theEnvironmentField.setAccessible(true);
Map<String, String> env = (Map<String, String>) theEnvironmentField.get(null);
env.putAll(newenv);
Field theCaseInsensitiveEnvironmentField = processEnvironmentClass.getDeclaredField("theCaseInsensitiveEnvironment");
theCaseInsensitiveEnvironmentField.setAccessible(true);
Map<String, String> cienv = (Map<String, String>) theCaseInsensitiveEnvironmentField.get(null);
cienv.putAll(newenv);
}
catch (NoSuchFieldException e)
{
try {
Class[] classes = Collections.class.getDeclaredClasses();
Map<String, String> env = System.getenv();
for(Class cl : classes) {
if("java.util.Collections$UnmodifiableMap".equals(cl.getName())) {
Field field = cl.getDeclaredField("m");
field.setAccessible(true);
Object obj = field.get(env);
Map<String, String> map = (Map<String, String>) obj;
map.putAll(newenv);
}
}
} catch (Exception e2) {
e2.printStackTrace();
}
} catch (Exception e1) {
e1.printStackTrace();
}
}

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