code: @Test public void testBuildEnvPropertiesWithPkgNull(){
    appender.setInitialContextFactoryName("icfn");
    appender.setProviderURL("url");
    appender.setURLPkgPrefixes(null);
    appender.setSecurityPrincipalName("user");
    appender.setSecurityCredentials("cred");
    Properties props=appender.buildEnvProperties();
    assertEquals(4,props.size());
    assertEquals(appender.getInitialContextFactoryName(),props.getProperty(Context.INITIAL_CONTEXT_FACTORY));
    assertEquals(appender.getProviderURL(),props.getProperty(Context.PROVIDER_URL));
    assertEquals(null,props.getProperty(Context.URL_PKG_PREFIXES));
    assertEquals(appender.getSecurityPrincipalName(),props.getProperty(Context.SECURITY_PRINCIPAL));
    assertEquals(appender.getSecurityCredentials(),props.getProperty(Context.SECURITY_CREDENTIALS));
    assertEquals(0,context.getStatusManager().getCount());
  }
  