*   protected void startUp() throws Exception {
 *     toCrawl = readStartingUris();
 *   }
 *
 *   protected void runOneIteration() throws Exception {
 *     Uri uri = toCrawl.remove();
 *     Collection<Uri> newUris = crawl(uri);
 *     visited.add(uri);
 *     for (Uri newUri : newUris) {
 *       if (!visited.contains(newUri)) { toCrawl.add(newUri); }
 *     }
 *   }
 *

---
title: Recipes
description: A collection of common/useful code examples for Kotlin and Java
---


# Recipes

We've written some recipes that demonstrate how to solve common problems with OkHttp. Read through them to learn about how everything works together. Cut-and-paste these examples freely; that's what they're for.

### Synchronous Get ([.kt][SynchronousGetKotlin], [.java][SynchronousGetJava])

func gridLogOnceIf(ctx context.Context, err error, id string, errKind ...interface{}) {
	logger.LogOnceIf(ctx, "grid", err, id, errKind...)
}

// A Connection is a remote connection.
// There is no distinction externally whether the connection was initiated from
// this server or from the remote.
type Connection struct {
	// NextID is the next ID that can be used (atomic).
	NextID uint64

	// LastPong is last pong time (atomic)

* Retry 'connection refused' errors when setting up clusters on GCE. ([#57394](https://github.com/kubernetes/kubernetes/pull/57394), [@mborsz](https://github.com/mborsz))
* Retry 'connection refused' errors when setting up clusters on GCE. ([#57394](https://github.com/kubernetes/kubernetes/pull/57394), [@mborsz](https://github.com/mborsz))

a struct with a <code>_size</code> field), <code>#include
"go_asm.h"</code> will fail with a "redefinition of macro" error.
</p>

<h3 id="runtime">Runtime Coordination</h3>

<p>
For garbage collection to run correctly, the runtime must know the
location of pointers in all global data and in most stack frames.
The Go compiler emits this information when compiling Go source files,

	ObjSizes      sizeHistogram     `msg:"szs"`
	ObjVersions   versionsHistogram `msg:"vh"`
	AllTierStats  *allTierStats     `msg:"ats,omitempty"`
	Compacted     bool              `msg:"c"`
}

// allTierStats is a collection of per-tier stats across all configured remote
// tiers.
type allTierStats struct {
	Tiers map[string]tierStats `msg:"ts"`
}

func newAllTierStats() *allTierStats {
	return &allTierStats{

## Metrics Request Handling

Each endpoint can be queried as needed via a scrape configuration in Prometheus or a compatible metrics collection tool. You should schedule scrape operations so a prior scrape completes before the next one begins.

 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.core.beans.util;

import static org.codelibs.core.collection.CollectionsUtil.newLinkedHashMap;
import static org.codelibs.core.misc.AssertionUtil.assertArgumentNotNull;

import java.util.Map;
import java.util.Map.Entry;
import java.util.function.Consumer;

#### Garbage Collector
* The garbage collector now supports custom APIs added via Custom Resource Definitions
  or aggregated API servers. The garbage collector controller refreshes periodically.
  Therefore, expect a latency of about 30 seconds between when an API is added and when
  the garbage collector starts to manage it.


#### Monitoring/Prometheus

 *
 * <p><b>Warning:</b> The comparison must be <i>consistent with equals</i> as explained by the
 * {@link Comparable} class specification. Otherwise, the resulting multiset will violate the {@link
 * java.util.Collection} contract, which is specified in terms of {@link Object#equals}.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#multiset">{@code Multiset}</a>.
 *