README.md

Create a standard mvn folder structure by putting each file in a folder like this:

├── pom.xml
└── src
    └── test
        ├── java
        │   └── UnknownHostExceptionTest.java
        └── resources
            └── trace.btm

Run with mvn test

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <name>curator-unknownhostexception</name>
  <modelVersion>4.0.0</modelVersion>
  <groupId>no.found</groupId>
  <artifactId>curator-unknownhostexception</artifactId>
  <version>0.1.0-SNAPSHOT</version>
  <packaging>jar</packaging>
  <description>Demo project to test handling of unknownhostexception</description>
  <inceptionYear>2014</inceptionYear>

  <properties>
    <byteman.version>2.1.4.1</byteman.version>
  </properties>
  <dependencies>
    <dependency>
      <groupId>org.apache.zookeeper</groupId>
      <artifactId>zookeeper</artifactId>
      <version>3.4.5</version>
      <scope>compile</scope>
      <exclusions>
        <exclusion>
          <groupId>org.jboss.netty</groupId>
          <artifactId>netty</artifactId>
        </exclusion>
        <exclusion>
          <groupId>junit</groupId>
          <artifactId>junit</artifactId>
        </exclusion>
        <exclusion>
          <groupId>jline</groupId>
          <artifactId>jline</artifactId>
        </exclusion>
        <exclusion>
          <groupId>log4j</groupId>
          <artifactId>log4j</artifactId>
        </exclusion>
      </exclusions>
    </dependency>
    <dependency>
      <groupId>log4j</groupId>
      <artifactId>log4j</artifactId>
      <version>1.2.17</version>
    </dependency>

    <dependency>
      <groupId>org.apache.curator</groupId>
      <artifactId>curator-recipes</artifactId>
      <version>2.4.0</version>
    </dependency>
    <dependency>
      <groupId>org.apache.curator</groupId>
      <artifactId>curator-test</artifactId>
      <version>2.4.0</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.11</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>org.easymock</groupId>
      <artifactId>easymock</artifactId>
      <version>3.1</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>org.jboss.byteman</groupId>
      <artifactId>byteman</artifactId>
      <scope>test</scope>
      <version>${byteman.version}</version>
    </dependency>
    <dependency>
      <groupId>org.jboss.byteman</groupId>
      <artifactId>byteman-submit</artifactId>
      <scope>test</scope>
      <version>${byteman.version}</version>
    </dependency>
    <dependency>
      <groupId>org.jboss.byteman</groupId>
      <artifactId>byteman-install</artifactId>
      <scope>test</scope>
      <version>${byteman.version}</version>
    </dependency>
    <dependency>
      <groupId>org.jboss.byteman</groupId>
      <artifactId>byteman-bmunit</artifactId>
      <scope>test</scope>
      <version>${byteman.version}</version>
    </dependency>
    <dependency>
      <groupId>com.sun</groupId>
      <artifactId>tools</artifactId>
      <version>1.6</version>
      <scope>system</scope>
      <systemPath>${java.home}/../lib/tools.jar</systemPath>
    </dependency>
  </dependencies>
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-surefire-plugin</artifactId>
        <!-- <version>2.4.3</version> -->
        <configuration>
          <useManifestOnlyJar>false</useManifestOnlyJar>
          <forkMode>once</forkMode>
          <parallel>false</parallel>
        </configuration>
      </plugin>
    </plugins>
  </build>
</project>

trace.btm

RULE make zookeeper throw unknownhostexception
CLASS org.apache.zookeeper.client.StaticHostProvider
METHOD <init>
AT ENTRY
IF true
DO traceln("***  Injecting UnknownHostException!");
throw new UnknownHostException()
ENDRULE

UnknownHostExceptionTest.java

import static org.junit.Assert.assertNotNull;

import java.io.IOException;
import java.util.concurrent.TimeUnit;

import org.apache.curator.RetryPolicy;
import org.apache.curator.RetrySleeper;
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.test.TestingServer;
import org.jboss.byteman.contrib.bmunit.BMScript;
import org.jboss.byteman.contrib.bmunit.BMUnitRunner;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;

@RunWith(BMUnitRunner.class)
@BMScript(value = "trace", dir = "target/test-classes")
public class UnknownHostExceptionTest {

    private TestingServer server;

    @Before
    public void setUp() throws Exception {
        server = new TestingServer();
    }

    @Test
    public void test() throws Exception {

        CuratorFramework client = CuratorFrameworkFactory.newClient(server.getConnectString(),
                new TryEverySecond());
        client.start();
        client.create().forPath("/foo");
        assertNotNull(client.checkExists().forPath("/foo"));
    }

    @After
    public void cleanUp() throws IOException {
        server.close();
    }

    static class TryEverySecond implements RetryPolicy {

        @Override
        public boolean allowRetry(int retryCount, long elapsedTimeMs, RetrySleeper sleeper) {
            try {
                sleeper.sleepFor(1000, TimeUnit.MILLISECONDS);
            } catch (InterruptedException e) {
                Thread.currentThread().interrupt();
                return false;
            }
            return true;
        }

    }
}