EnvSetup.java

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package edu.isi.pegasus.planner.test;

import java.lang.reflect.Field;
import java.util.Collections;
import java.util.Map;

/**
 * A utility class that sets up the environment for junit tests
 * 
 * 
 * @author vahi
 */
public class EnvSetup {
    /**
     * Hackish way to setup environment for JUnit test cases.
     * Only use for test cases, and not anwyhere else in production code.
     * 
     * http://stackoverflow.com/questions/318239/how-do-i-set-environment-variables-from-java
     * 
     */
    public static void setEnvironmentVariables(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.clear();
                        map.putAll( newEnv );
                    }
                }
            } catch (Exception e2) {
                e2.printStackTrace();
            }
        } catch (Exception e1) {
            e1.printStackTrace();
        }
    }
    
}