latest/pt/examples/mp-faulttolerance-retry.html - tomee-site-pub - Git at Google

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               <h1>MicroProfile Fault Tolerance - Retry Policy</h1>
             </div>
           </div>
         </div>
         <div class="row">

             <div class="col-md-12">
                 <div id="preamble">
 <div class="sectionbody">
 <div class="paragraph">
 <p>Este é um exemplo de como usar
 Microprofile @Retry em TomEE.</p>
 </div>
 </div>
 </div>
 <div class="sect1">
 <h2 id="_retry_feature">Retry Feature</h2>
 <div class="sectionbody">
 <div class="paragraph">
 <p>Microprofile Fault Tolerance tem um recurso chamado Retry que pode ser usado
 para recuperar uma operação de falha, chamando a mesma operação novamente
 até atingir seus critérios de parada.</p>
 </div>
 <div class="paragraph">
 <p>A Retry policy permite configurar :</p>
 </div>
 <div class="ulist">
 <ul>
 <li>
 <p><strong>maxRetries</strong>: o máximo de tentativas</p>
 </li>
 <li>
 <p><strong>delay</strong>: atrasos entre cada tentativa</p>
 </li>
 <li>
 <p><strong>delayUnit</strong>: a unidade de atraso</p>
 </li>
 <li>
 <p><strong>maxDuration</strong>: duração máxima para executar a nova tentativa</p>
 </li>
 <li>
 <p><strong>durationUnit</strong>: unidade de duração</p>
 </li>
 <li>
 <p><strong>jitter:</strong> a variação aleatória dos atrasos de uma nova tentativa</p>
 </li>
 <li>
 <p><strong>jitterDelayUnit:</strong> a unidade de instabilidade</p>
 </li>
 <li>
 <p><strong>retryOn:</strong> especifique as falhas para tentar novamente</p>
 </li>
 <li>
 <p><strong>abortOn:</strong> especifique as falhas para abortar</p>
 </li>
 </ul>
 </div>
 <div class="paragraph">
 <p>Para usar esse recurso, você pode anotar uma classe e/ou um método com a anotação @Retry. Verifique em
 <a href="http://download.eclipse.org/microprofile/microprofile-fault-tolerance-1.1/microprofile-fault-tolerance-spec.html">specification</a>
 para mais detalhes.</p>
 </div>
 </div>
 </div>
 <div class="sect1">
 <h2 id="_exemplos">Exemplos</h2>
 <div class="sectionbody">
 <div class="sect2">
 <h3 id="_execute_o_aplicativo">Execute o aplicativo</h3>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">mvn clean install tomee:run</code></pre>
 </div>
 </div>
 </div>
 <div class="sect2">
 <h3 id="_exemplo_1">Exemplo 1</h3>
 <div class="paragraph">
 <p>O método statusOfDay falhará 3 (três) vezes, a cada vez, lançando uma
 <code>WeatherGatewayTimeoutException</code> e como a anotação @Retry está
 configurada para <code>retryOn</code> em caso de falha, a biblioteca FailSafe pegará
 o valor <code>maxRetry</code> e tentará a mesma operação até atingir o número máximo de tentativas, que é 3 (valor padrão).</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">@RequestScoped
 public class WeatherGateway{
    ...
    @Retry(maxRetry=3, retryOn = WeatherGatewayTimeoutException.class)
    public String statusOfDay(){
        if(counterStatusOfDay.addAndGet(1) &lt;= DEFAULT_MAX_RETRY){
            LOGGER.warning(String.format(FORECAST_TIMEOUT_MESSAGE, DEFAULT_MAX_RETRY, counterStatusOfDay.get()));
            throw new WeatherGatewayTimeoutException();
        }
        return "Today is a sunny day!";
    }
    ...
  }</code></pre>
 </div>
 </div>
 <div class="paragraph">
 <p>Chamada de status do dia</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">GET http://localhost:8080/mp-faulttolerance-retry/weather/day/status</code></pre>
 </div>
 </div>
 <div class="paragraph">
 <p>Server log</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">WARNING - Timeout when accessing AccuWeather Forecast Service. Max of Attempts: (3), Attempts: (1)
 WARNING - Timeout when accessing AccuWeather Forecast Service. Max of Attempts: (3), Attempts: (2)
 WARNING - Timeout when accessing AccuWeather Forecast Service. Max of Attempts: (3), Attempts: (3)</code></pre>
 </div>
 </div>
 <div class="paragraph">
 <p>Response</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">Today is a sunny day!</code></pre>
 </div>
 </div>
 </div>
 <div class="sect2">
 <h3 id="_exemplo_2">Exemplo 2</h3>
 <div class="paragraph">
 <p>O método weekStatus falhará duas vezes, a cada vez, lançando uma
 <code>WeatherGatewayTimeoutException</code> porque <code>retryOn</code> está configurado e
 em vez de retornar uma resposta ao chamador, a lógica afirma que na terceira tentativa uma
 <code>WeatherGatewayBusyServiceException</code> será lançada. Como a anotação <code>@Retry</code> está configurada para
  <code>abortOn</code> no caso de <code>WeatherGatewayTimeoutException</code> ocorrer, a tentativa restante não será
 executada e o chamador deve lidar com a exceção.</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">@Retry(maxRetries = 3, retryOn = WeatherGatewayTimeoutException.class, abortOn = WeatherGatewayBusyServiceException.class)
 public String statusOfWeek(){
     if(counterStatusOfWeek.addAndGet(1) &lt;= DEFAULT_MAX_RETRY){
         LOGGER.warning(String.format(FORECAST_TIMEOUT_MESSAGE_ATTEMPTS, DEFAULT_MAX_RETRY, counterStatusOfWeek.get()));
         throw new WeatherGatewayTimeoutException();
     }
     LOGGER.log(Level.SEVERE, String.format(FORECAST_BUSY_MESSAGE, counterStatusOfWeek.get()));
     throw new WeatherGatewayBusyServiceException();
 }</code></pre>
 </div>
 </div>
 <div class="paragraph">
 <p>Chamada de status da semana</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">GET http://localhost:8080/mp-faulttolerance-retry/weather/week/status</code></pre>
 </div>
 </div>
 <div class="paragraph">
 <p>Server log</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">WARNING - Timeout when accessing AccuWeather Forecast Service. Max of Attempts: (3), Attempts: (1)
 WARNING - Timeout when accessing AccuWeather Forecast Service. Max of Attempts: (3), Attempts: (2)
 WARNING - Timeout when accessing AccuWeather Forecast Service. Max of Attempts: (3), Attempts: (3)
 SEVERE  - Error AccuWeather Forecast Service is busy. Number of Attempts: (4)</code></pre>
 </div>
 </div>
 <div class="paragraph">
 <p>Response</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">WeatherGateway Service is Busy. Retry later</code></pre>
 </div>
 </div>
 </div>
 <div class="sect2">
 <h3 id="_exemplo_3">Exemplo 3</h3>
 <div class="paragraph">
 <p>A anotação <code>@Retry</code> permite configurar um atraso para cada nova tentativa
 ser executada, dando a chance ao serviço solicitado para se recuperar e
 responder a solicitação corretamente. Para cada nova tentativa, seguindo o atraso
 configurado, é necessário definir <code>jitter</code> como zero (0). Caso contrário, o atraso de
 cada nova tentativa será aleatório.</p>
 </div>
 <div class="paragraph">
 <p>Analisando o log de mensagens, é possível ver que todas as tentativas levaram
 praticamente o mesmo tempo para executar.</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">@Retry(retryOn = WeatherGatewayTimeoutException.class, maxRetries = 5, delay = 500, jitter = 0)
 public String statusOfWeekend() {
     if (counterStatusOfWeekend.addAndGet(1) &lt;= 5) {
         logTimeoutMessage(statusOfWeekendInstant);
         statusOfWeekendInstant = Instant.now();
         throw new WeatherGatewayTimeoutException();
     }
     return "The Forecast for the Weekend is Scattered Showers.";
 }</code></pre>
 </div>
 </div>
 <div class="paragraph">
 <p>Chamada de status de fim de semana</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">GET http://localhost:8080/mp-faulttolerance-retry/weather/weekend/status</code></pre>
 </div>
 </div>
 <div class="paragraph">
 <p>Server log</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">WARNING - Timeout when accessing AccuWeather Forecast Service.
 WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (501) millis
 WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (501) millis
 WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (501) millis
 WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (500) millis</code></pre>
 </div>
 </div>
 </div>
 <div class="sect2">
 <h3 id="_exemplo_4">Exemplo 4</h3>
 <div class="paragraph">
 <p>Basicamente com o mesmo comportamento do <code>Exemplo 3</code>, este exemplo defini
 o <code>delay</code> e o <code>jitter</code> com 500 milissegundos para aleatoriamente um novo atraso a cada nova tentativa
 após a primeira falha.
 <a href="https://github.com/jhalterman/failsafe/blob/master/src/main/java/net/jodah/failsafe/AbstractExecution.java">AbstractExecution#randomDelay(delay,jitter,random)</a>
 pode dar uma ideia de como o novo atraso é calculado.</p>
 </div>
 <div class="paragraph">
 <p>Analisando o log de mensagens, é possível ver quanto tempo cada tentativa teve
 que esperar até a sua execução.</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">@Retry(retryOn = WeatherGatewayTimeoutException.class, delay = 500, jitter = 500)
 public String statusOfMonth() {
     if (counterStatusOfWeekend.addAndGet(1) &lt;= DEFAULT_MAX_RETRY) {
         logTimeoutMessage(statusOfMonthInstant);
         statusOfMonthInstant = Instant.now();
         throw new WeatherGatewayTimeoutException();
     }
     return "The Forecast for the Weekend is Scattered Showers.";
 }</code></pre>
 </div>
 </div>
 <div class="paragraph">
 <p>Chamada de status do mês</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">GET http://localhost:8080/mp-faulttolerance-retry/weather/month/status</code></pre>
 </div>
 </div>
 <div class="paragraph">
 <p>Server log</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">WARNING - Timeout when accessing AccuWeather Forecast Service.
 WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (417) millis
 WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (90) millis</code></pre>
 </div>
 </div>
 </div>
 <div class="sect2">
 <h3 id="_example_5">Example 5</h3>
 <div class="paragraph">
 <p>Se uma condição para uma operação re-executada não estiver definida como nos
 exemplos anteriores usando o parâmetro <code>retryOn</code>, a operação é
 executada novamente para qualquer exceção lançada.</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">@Retry(maxDuration = 1000)
 public String statusOfYear(){
     if (counterStatusOfWeekend.addAndGet(1) &lt;= 5) {
         logTimeoutMessage(statusOfYearInstant);
         statusOfYearInstant = Instant.now();
         throw new RuntimeException();
     }
     return "WeatherGateway Service Error";
 }</code></pre>
 </div>
 </div>
 <div class="paragraph">
 <p>Chamada de status do ano</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">GET http://localhost:8080/mp-faulttolerance-retry/weather/year/statusk</code></pre>
 </div>
 </div>
 <div class="paragraph">
 <p>Server log</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">WARNING - Timeout when accessing AccuWeather Forecast Service.
 WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (666) millis
 WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (266) millis
 WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (66) millis</code></pre>
 </div>
 </div>
 </div>
 <div class="sect2">
 <h3 id="_execute_os_testes">Execute os testes</h3>
 <div class="paragraph">
 <p>Você também pode experimentar usando
 <a href="src/test/java/org/superbiz/rest/WeatherServiceTest.java">WeatherServiceTest.java</a>
 disponível no projeto.</p>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">mvn clean test</code></pre>
 </div>
 </div>
 <div class="listingblock">
 <div class="content">
 <pre class="highlight"><code class="language-java" data-lang="java">[INFO] Results:
 [INFO]
 [INFO] Tests run: 5, Failures: 0, Errors: 0, Skipped: 0</code></pre>
 </div>
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	<div class='page-header'>

	<h1>MicroProfile Fault Tolerance - Retry Policy</h1>
	</div>
	</div>
	</div>
	<div class="row">

	<div class="col-md-12">
	<div id="preamble">
	<div class="sectionbody">
	<div class="paragraph">
	<p>Este é um exemplo de como usar
	Microprofile @Retry em TomEE.</p>
	</div>
	</div>
	</div>
	<div class="sect1">
	<h2 id="_retry_feature">Retry Feature</h2>
	<div class="sectionbody">
	<div class="paragraph">
	<p>Microprofile Fault Tolerance tem um recurso chamado Retry que pode ser usado
	para recuperar uma operação de falha, chamando a mesma operação novamente
	até atingir seus critérios de parada.</p>
	</div>
	<div class="paragraph">
	<p>A Retry policy permite configurar :</p>
	</div>
	<div class="ulist">
	<ul>
	<li>
	<p><strong>maxRetries</strong>: o máximo de tentativas</p>
	</li>
	<li>
	<p><strong>delay</strong>: atrasos entre cada tentativa</p>
	</li>
	<li>
	<p><strong>delayUnit</strong>: a unidade de atraso</p>
	</li>
	<li>
	<p><strong>maxDuration</strong>: duração máxima para executar a nova tentativa</p>
	</li>
	<li>
	<p><strong>durationUnit</strong>: unidade de duração</p>
	</li>
	<li>
	<p><strong>jitter:</strong> a variação aleatória dos atrasos de uma nova tentativa</p>
	</li>
	<li>
	<p><strong>jitterDelayUnit:</strong> a unidade de instabilidade</p>
	</li>
	<li>
	<p><strong>retryOn:</strong> especifique as falhas para tentar novamente</p>
	</li>
	<li>
	<p><strong>abortOn:</strong> especifique as falhas para abortar</p>
	</li>
	</ul>
	</div>
	<div class="paragraph">
	<p>Para usar esse recurso, você pode anotar uma classe e/ou um método com a anotação @Retry. Verifique em
	<a href="http://download.eclipse.org/microprofile/microprofile-fault-tolerance-1.1/microprofile-fault-tolerance-spec.html">specification</a>
	para mais detalhes.</p>
	</div>
	</div>
	</div>
	<div class="sect1">
	<h2 id="_exemplos">Exemplos</h2>
	<div class="sectionbody">
	<div class="sect2">
	<h3 id="_execute_o_aplicativo">Execute o aplicativo</h3>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">mvn clean install tomee:run</code></pre>
	</div>
	</div>
	</div>
	<div class="sect2">
	<h3 id="_exemplo_1">Exemplo 1</h3>
	<div class="paragraph">
	<p>O método statusOfDay falhará 3 (três) vezes, a cada vez, lançando uma
	<code>WeatherGatewayTimeoutException</code> e como a anotação @Retry está
	configurada para <code>retryOn</code> em caso de falha, a biblioteca FailSafe pegará
	o valor <code>maxRetry</code> e tentará a mesma operação até atingir o número máximo de tentativas, que é 3 (valor padrão).</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">@RequestScoped
	public class WeatherGateway{
	...
	@Retry(maxRetry=3, retryOn = WeatherGatewayTimeoutException.class)
	public String statusOfDay(){
	if(counterStatusOfDay.addAndGet(1) <= DEFAULT_MAX_RETRY){
	LOGGER.warning(String.format(FORECAST_TIMEOUT_MESSAGE, DEFAULT_MAX_RETRY, counterStatusOfDay.get()));
	throw new WeatherGatewayTimeoutException();
	}
	return "Today is a sunny day!";
	}
	...
	}</code></pre>
	</div>
	</div>
	<div class="paragraph">
	<p>Chamada de status do dia</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">GET http://localhost:8080/mp-faulttolerance-retry/weather/day/status</code></pre>
	</div>
	</div>
	<div class="paragraph">
	<p>Server log</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">WARNING - Timeout when accessing AccuWeather Forecast Service. Max of Attempts: (3), Attempts: (1)
	WARNING - Timeout when accessing AccuWeather Forecast Service. Max of Attempts: (3), Attempts: (2)
	WARNING - Timeout when accessing AccuWeather Forecast Service. Max of Attempts: (3), Attempts: (3)</code></pre>
	</div>
	</div>
	<div class="paragraph">
	<p>Response</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">Today is a sunny day!</code></pre>
	</div>
	</div>
	</div>
	<div class="sect2">
	<h3 id="_exemplo_2">Exemplo 2</h3>
	<div class="paragraph">
	<p>O método weekStatus falhará duas vezes, a cada vez, lançando uma
	<code>WeatherGatewayTimeoutException</code> porque <code>retryOn</code> está configurado e
	em vez de retornar uma resposta ao chamador, a lógica afirma que na terceira tentativa uma
	<code>WeatherGatewayBusyServiceException</code> será lançada. Como a anotação <code>@Retry</code> está configurada para
	<code>abortOn</code> no caso de <code>WeatherGatewayTimeoutException</code> ocorrer, a tentativa restante não será
	executada e o chamador deve lidar com a exceção.</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">@Retry(maxRetries = 3, retryOn = WeatherGatewayTimeoutException.class, abortOn = WeatherGatewayBusyServiceException.class)
	public String statusOfWeek(){
	if(counterStatusOfWeek.addAndGet(1) <= DEFAULT_MAX_RETRY){
	LOGGER.warning(String.format(FORECAST_TIMEOUT_MESSAGE_ATTEMPTS, DEFAULT_MAX_RETRY, counterStatusOfWeek.get()));
	throw new WeatherGatewayTimeoutException();
	}
	LOGGER.log(Level.SEVERE, String.format(FORECAST_BUSY_MESSAGE, counterStatusOfWeek.get()));
	throw new WeatherGatewayBusyServiceException();
	}</code></pre>
	</div>
	</div>
	<div class="paragraph">
	<p>Chamada de status da semana</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">GET http://localhost:8080/mp-faulttolerance-retry/weather/week/status</code></pre>
	</div>
	</div>
	<div class="paragraph">
	<p>Server log</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">WARNING - Timeout when accessing AccuWeather Forecast Service. Max of Attempts: (3), Attempts: (1)
	WARNING - Timeout when accessing AccuWeather Forecast Service. Max of Attempts: (3), Attempts: (2)
	WARNING - Timeout when accessing AccuWeather Forecast Service. Max of Attempts: (3), Attempts: (3)
	SEVERE - Error AccuWeather Forecast Service is busy. Number of Attempts: (4)</code></pre>
	</div>
	</div>
	<div class="paragraph">
	<p>Response</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">WeatherGateway Service is Busy. Retry later</code></pre>
	</div>
	</div>
	</div>
	<div class="sect2">
	<h3 id="_exemplo_3">Exemplo 3</h3>
	<div class="paragraph">
	<p>A anotação <code>@Retry</code> permite configurar um atraso para cada nova tentativa
	ser executada, dando a chance ao serviço solicitado para se recuperar e
	responder a solicitação corretamente. Para cada nova tentativa, seguindo o atraso
	configurado, é necessário definir <code>jitter</code> como zero (0). Caso contrário, o atraso de
	cada nova tentativa será aleatório.</p>
	</div>
	<div class="paragraph">
	<p>Analisando o log de mensagens, é possível ver que todas as tentativas levaram
	praticamente o mesmo tempo para executar.</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">@Retry(retryOn = WeatherGatewayTimeoutException.class, maxRetries = 5, delay = 500, jitter = 0)
	public String statusOfWeekend() {
	if (counterStatusOfWeekend.addAndGet(1) <= 5) {
	logTimeoutMessage(statusOfWeekendInstant);
	statusOfWeekendInstant = Instant.now();
	throw new WeatherGatewayTimeoutException();
	}
	return "The Forecast for the Weekend is Scattered Showers.";
	}</code></pre>
	</div>
	</div>
	<div class="paragraph">
	<p>Chamada de status de fim de semana</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">GET http://localhost:8080/mp-faulttolerance-retry/weather/weekend/status</code></pre>
	</div>
	</div>
	<div class="paragraph">
	<p>Server log</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">WARNING - Timeout when accessing AccuWeather Forecast Service.
	WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (501) millis
	WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (501) millis
	WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (501) millis
	WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (500) millis</code></pre>
	</div>
	</div>
	</div>
	<div class="sect2">
	<h3 id="_exemplo_4">Exemplo 4</h3>
	<div class="paragraph">
	<p>Basicamente com o mesmo comportamento do <code>Exemplo 3</code>, este exemplo defini
	o <code>delay</code> e o <code>jitter</code> com 500 milissegundos para aleatoriamente um novo atraso a cada nova tentativa
	após a primeira falha.
	<a href="https://github.com/jhalterman/failsafe/blob/master/src/main/java/net/jodah/failsafe/AbstractExecution.java">AbstractExecution#randomDelay(delay,jitter,random)</a>
	pode dar uma ideia de como o novo atraso é calculado.</p>
	</div>
	<div class="paragraph">
	<p>Analisando o log de mensagens, é possível ver quanto tempo cada tentativa teve
	que esperar até a sua execução.</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">@Retry(retryOn = WeatherGatewayTimeoutException.class, delay = 500, jitter = 500)
	public String statusOfMonth() {
	if (counterStatusOfWeekend.addAndGet(1) <= DEFAULT_MAX_RETRY) {
	logTimeoutMessage(statusOfMonthInstant);
	statusOfMonthInstant = Instant.now();
	throw new WeatherGatewayTimeoutException();
	}
	return "The Forecast for the Weekend is Scattered Showers.";
	}</code></pre>
	</div>
	</div>
	<div class="paragraph">
	<p>Chamada de status do mês</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">GET http://localhost:8080/mp-faulttolerance-retry/weather/month/status</code></pre>
	</div>
	</div>
	<div class="paragraph">
	<p>Server log</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">WARNING - Timeout when accessing AccuWeather Forecast Service.
	WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (417) millis
	WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (90) millis</code></pre>
	</div>
	</div>
	</div>
	<div class="sect2">
	<h3 id="_example_5">Example 5</h3>
	<div class="paragraph">
	<p>Se uma condição para uma operação re-executada não estiver definida como nos
	exemplos anteriores usando o parâmetro <code>retryOn</code>, a operação é
	executada novamente para qualquer exceção lançada.</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">@Retry(maxDuration = 1000)
	public String statusOfYear(){
	if (counterStatusOfWeekend.addAndGet(1) <= 5) {
	logTimeoutMessage(statusOfYearInstant);
	statusOfYearInstant = Instant.now();
	throw new RuntimeException();
	}
	return "WeatherGateway Service Error";
	}</code></pre>
	</div>
	</div>
	<div class="paragraph">
	<p>Chamada de status do ano</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">GET http://localhost:8080/mp-faulttolerance-retry/weather/year/statusk</code></pre>
	</div>
	</div>
	<div class="paragraph">
	<p>Server log</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">WARNING - Timeout when accessing AccuWeather Forecast Service.
	WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (666) millis
	WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (266) millis
	WARNING - Timeout when accessing AccuWeather Forecast Service. Delay before this attempt: (66) millis</code></pre>
	</div>
	</div>
	</div>
	<div class="sect2">
	<h3 id="_execute_os_testes">Execute os testes</h3>
	<div class="paragraph">
	<p>Você também pode experimentar usando
	<a href="src/test/java/org/superbiz/rest/WeatherServiceTest.java">WeatherServiceTest.java</a>
	disponível no projeto.</p>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">mvn clean test</code></pre>
	</div>
	</div>
	<div class="listingblock">
	<div class="content">
	<pre class="highlight"><code class="language-java" data-lang="java">[INFO] Results:
	[INFO]
	[INFO] Tests run: 5, Failures: 0, Errors: 0, Skipped: 0</code></pre>
	</div>
	</div>
	</div>
	</div>
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