logback-android/src/main/java/ch/qos/logback/core/util/OptionHelper.java
public static String getEnv(String key) {
    try {
      return System.getenv(key);
    } catch (SecurityException e) {
      return null;
    }
  }
public static String getEnv(String key) {
    try {
      return System.getenv(key);
    } catch (SecurityException e) {
      return null;
    }
  }
public static String getEnv ( String key ) { try { return System . getenv ( key ) ; } catch ( SecurityException e ) { return null ; } }
Lookup a key from the environment.

@param key the environment variable's key
@return value corresponding to key from the OS environment
Lookup a key from the environment .