# Controllers

Istio has a variety of [controllers](https://kubernetes.io/docs/concepts/architecture/controller/), which basically watch some inputs and do something.
This can be reading from Kubernetes and writing other objects back, writing to proxies over XDS, etc.

Unfortunately, writing controllers is very error prone, even for seemingly simple cases.
To work around this, Istio has a variety of abstractions meant to make writing controllers easier.

## Clients

        accessResultDataImpl.setTransformerName("transformer");

        setBaseDir();

        try {
            final Object obj = fileTransformer.getData(accessResultDataImpl);
            fail();
        } catch (final CrawlerSystemException e) {}
    }

    public void test_getData_nullData() throws Exception {
        final AccessResultDataImpl accessResultDataImpl = new AccessResultDataImpl();

                    raf.seek(6);
                    try {
                        raf.readFully(buf);
                        Assert.fail("Should have thrown exception");
                    }
                    catch ( SmbEndOfFileException e ) {}
                }

            }
            finally {
                f.delete();
            }
        }
    }


    @Test

set args=
:argsloop
if not "%~1"=="" (
  rem Checks if the argument contains "-D" and if true, adds argument 1 with 2 and puts an equal sign between them.
  rem This is done since batch considers "=" to be a delimiter so we need to circumvent this behavior with a small hack.
  set arg1=%~1
  if "!arg1:~0,2!"=="-D" (
   	set "args=%args% "%~1"="%~2""
    shift
    shift
    goto argsloop
  )

        }
        Map<String, Object> target = dataMap;
        for (final Ingester ingester : ingestFactory.getIngesters()) {
            try {
                target = ingester.process(target, paramMap);
            } catch (final Exception e) {
                logger.warn("Failed to process Ingest[{}]", ingester.getClass().getSimpleName(), e);
            }
        }
        return target;
    }

    @Override

            builder.flush();
            try (OutputStream out = builder.getOutputStream()) {
                stats = ((ByteArrayOutputStream) out).toString(Constants.UTF_8);
            }
        } catch (final Exception e) {
            appendException(buf, e).append(',');
        }
        buf.append("\"search_engine\":").append(stats).append(',');
    }

      SortedMap<@Nullable Object, V> self = (SortedMap<@Nullable Object, V>) this;
      Object ceilingKey = self.tailMap(key).firstKey();
      return unsafeCompare(comparator(), ceilingKey, key) == 0;
    } catch (ClassCastException | NoSuchElementException | NullPointerException e) {
      return false;
    }
  }

  /**
   * A sensible default implementation of {@link #subMap(Object, Object)} in terms of {@link

                break;
            default:
                Assume.assumeTrue("Unhandled OEM encoding " + oemEncoding, false);
            }
        }
        catch ( UnsupportedCharsetException e ) {
            Assume.assumeTrue("Charset is not supported on this VM " + oemEncoding, false);
        }
        runFilenameTest(splitString(str, 8));
    }

            // System.err.println("Linked("+requestedScope+")
            // subgraph("+linkedRes.getVertices().size()+"):\n"+linkedRes.toString());
            return findLinkedSubgraph(res);
        } catch (MetadataResolutionException e) {
            throw new GraphConflictResolutionException(e);
        }
    }

    // -------------------------------------------------------------------------------------

        try {
            return registry != null
                    ? registry.stream().collect(Collectors.toMap(lf -> lf.id(), lf -> new Lifecycle(registry, lf)))
                    : Map.of();
        } catch (LookupException e) {
            throw new IllegalStateException("Unable to lookup lifecycles from the plexus container", e);
        }
    }

    public String getLifecyclePhaseList() {