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Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD

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package com.yammer.dropwizard.json;

import com.fasterxml.jackson.databind.PropertyNamingStrategy;
import com.fasterxml.jackson.databind.cfg.MapperConfig;
import com.fasterxml.jackson.databind.introspect.AnnotatedField;
import com.fasterxml.jackson.databind.introspect.AnnotatedMethod;
import com.fasterxml.jackson.databind.introspect.AnnotatedParameter;

/**
 * A {@link PropertyNamingStrategy} implementation which, if the declaring class of a property is

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Running commands on several remote hosts using ssh and xargs
There are a few different ways to run commands on groups or clusters of remote nodes, depending upon how complex the command.

Assuming your machines are named "node01" - "node22" :


# Run a command in parallel on all remote nodes
# results come back in random order as they are received.
pdsh -w "node[01-22]" df

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AliasesExist HEAD /_alias/{name}
AliasesExist HEAD /{index}/_alias/{name}
Analyze GET /_analyze
Analyze GET /{index}/_analyze
Analyze POST /_analyze
Analyze POST /{index}/_analyze
Bulk POST /_bulk
Bulk POST /{index}/_bulk
Bulk POST /{index}/{type}/_bulk
Bulk PUT /_bulk

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// Skip compiling and running tests
mvn package -Dmaven.test.skip=true

// Skip running tests in the Jar but compile (and include) them in the jar
mvn package -DskipTests

//
mvn package

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AssistedInject allows you to dynamically configure Factory for class instead of coding it by yourself. This is often useful when you have an object that has a dependencies that should be injected and some parameters that must be specified during creation of object.

Example from docummentaiton is a RealPayment

public class RealPayment implements Payment {
   @Inject
   public RealPayment(
      CreditService creditService,
      AuthService authService,
      @Assisted Date startDate,

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// CheckedProvider is an interface, which is a part of extension guice-throwingproviders.
public interface CheckedProvider<T> {
  T get() throws Exception;
}

// Injection 
@Inject
private ExcelCheckedProvider<FlightSupplier> excelCheckedProvider;

// Binding

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bindConstant().
annotatedWith(Names.named("maxResults")).
to(10);    
  
  @Inject
  public void setMaxResults(@Named("maxResults")int maxResults) {
    this.maxResults = maxResults;
  }

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public class DelivererBuilder {
    private final MailServerFinder finder;
    private Newsletter newsletter;
    private String mailServerUrl;
    private int port;
    
    @Inject
    public DelivererBuilder(MailServerFinder finder) {
        this.finder = finder;
    }

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public Deliverer buildDeliverer() {
    try {
        return new Deliverer(letter, mailServerUrl, port);
    } finally {
        letter = null;
        mailServerUrl = null;
        port = -1;
    } 
}