Dropwizard Example using Raw Jetty

DropRawApplication.java

package com.example;

import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.core.JsonGenerator;
import com.google.common.base.Strings;
import io.dropwizard.Application;
import io.dropwizard.setup.Environment;
import org.eclipse.jetty.servlet.ServletHolder;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.concurrent.atomic.AtomicLong;

public class DropRawApplication extends Application<DropRawConfiguration> {
    public static void main(final String[] args) throws Exception {
        new DropRawApplication().run(args);
    }

    @Override
    public String getName() {
        return "DropRaw";
    }

    @Override
    public void run(final DropRawConfiguration config,
                    final Environment env) {
        final DropRawServlet servlet = new DropRawServlet(env.getObjectMapper().getFactory(),
                config.getTemplate(), config.getDefaultName());
        env.getApplicationContext().addServlet(new ServletHolder(servlet), "/perf");
    }


    public static class DropRawServlet extends HttpServlet {
        private final JsonFactory jsonFactory;
        private final String template;
        private final String defaultName;
        private final AtomicLong counter = new AtomicLong();

        public DropRawServlet(JsonFactory jsonFactory, String template, String defaultName) {
            this.jsonFactory = jsonFactory;
            this.template = template;
            this.defaultName = defaultName ;
        }

        @Override
        protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
            final String name = Strings.nullToEmpty(req.getParameter("name"));
            resp.setContentType("application/json");

            if (name.length() > 5) {
                resp.setStatus(HttpServletResponse.SC_BAD_REQUEST);
                try (final JsonGenerator json = jsonFactory.createGenerator(resp.getOutputStream())) {
                    json.writeStartObject();
                    json.writeStringField("error", "Query parameter name must be shorter than 5 letters");
                    json.writeEndObject();
                    return;
                }
            }

            resp.setStatus(HttpServletResponse.SC_OK);
            try (final JsonGenerator json = jsonFactory.createGenerator(resp.getOutputStream())) {
                json.writeStartObject();
                json.writeNumberField("id", counter.incrementAndGet());
                json.writeStringField("content", String.format(template, name.length() != 0 ? name : defaultName));
                json.writeEndObject();
            }
        }
    }
}

JettyServlet.java

package com.example.raw.jetty;

import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.core.JsonGenerator;
import com.google.common.base.Strings;
import org.eclipse.jetty.server.Server;
import org.eclipse.jetty.servlet.ServletHandler;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.concurrent.atomic.AtomicLong;

/** Replicates the same happy path as the Dropwizard getting started example without
 *  and configuration builtin
 */
public class JettyServlet {
    private static final String defaultName = "Nick" ;
    private static final String template = "Hello %s!";
    private static final JsonFactory jsonFactory = new JsonFactory();
    private static final AtomicLong counter = new AtomicLong();

    public static void main( String[] args ) throws Exception {
        Server server = new Server(8095);
        ServletHandler handler = new ServletHandler();
        server.setHandler(handler);
        handler.addServletWithMapping(DropwizardExampleHandler.class, "/*");
        server.start();
        server.join();
    }

    public static class DropwizardExampleHandler extends HttpServlet {
        @Override
        protected void doGet(HttpServletRequest request, HttpServletResponse response )
                throws ServletException, IOException {
            final String name = Strings.nullToEmpty(request.getParameter("name"));
            response.setContentType("application/json");
            if (name.length() > 5) {
                response.setStatus(HttpServletResponse.SC_BAD_REQUEST);
                try (final JsonGenerator json = jsonFactory.createGenerator(response.getOutputStream())) {
                    json.writeStartObject();
                    json.writeStringField("error", "Query parameter name must be shorter than 5 letters");
                    json.writeEndObject();
                    return;
                }
            }

            response.setStatus(HttpServletResponse.SC_OK);
            try (final JsonGenerator json = jsonFactory.createGenerator(response.getOutputStream())) {
                json.writeStartObject();
                json.writeNumberField("id", counter.incrementAndGet());
                json.writeStringField("content", String.format(template, name.length() != 0 ? name : defaultName));
                json.writeEndObject();
            }
        }
    }
}

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">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.example</groupId>
    <artifactId>raw-jetty</artifactId>
    <version>1.0-SNAPSHOT</version>


    <dependencies>
        <dependency>
            <!-- this is required because jetty-server pom
            put servlet-api into default scope when it should
            always be provided scope so it doesn't get compiled.
            without this there are security exceptions because
            javax.servlet-api jar is not signed -->
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>4.0.0-b01</version>
            <!--<scope>provided</scope>-->
        </dependency>
        <dependency>
            <groupId>org.eclipse.jetty</groupId>
            <artifactId>jetty-server</artifactId>
            <version>9.3.7.v20160115</version>
        </dependency>
        <dependency>
            <groupId>org.eclipse.jetty</groupId>
            <artifactId>jetty-servlet</artifactId>
            <version>9.3.7.v20160115</version>
        </dependency>
        <dependency>
            <groupId>org.eclipse.jetty</groupId>
            <artifactId>jetty-servlets</artifactId>
            <version>9.3.7.v20160115</version>
        </dependency>
        <dependency>
            <groupId>org.eclipse.jetty</groupId>
            <artifactId>jetty-http</artifactId>
            <version>9.3.7.v20160115</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.7.1</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.7.1-1</version>
        </dependency>
        <dependency>
            <groupId>com.google.guava</groupId>
            <artifactId>guava</artifactId>
            <version>19.0</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>2.3.2</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <optimize>true</optimize>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-shade-plugin</artifactId>
                <version>1.6</version>
                <configuration>
                    <createDependencyReducedPom>true</createDependencyReducedPom>
                    <filters>
                        <filter>
                            <artifact>*:*</artifact>
                            <excludes>
                                <exclude>META-INF/*.SF</exclude>
                                <exclude>META-INF/*.DSA</exclude>
                                <exclude>META-INF/*.RSA</exclude>
                            </excludes>
                        </filter>
                    </filters>
                </configuration>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>shade</goal>
                        </goals>
                        <configuration>
                            <transformers>
                                <transformer implementation="org.apache.maven.plugins.shade.resource.ServicesResourceTransformer" />
                                <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                                    <mainClass>com.example.raw.jetty.RawJetty</mainClass>
                                </transformer>
                            </transformers>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

RawJetty.java

package com.example.raw.jetty;

import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.core.JsonGenerator;
import com.google.common.base.Strings;
import org.eclipse.jetty.http.HttpField;
import org.eclipse.jetty.http.HttpHeader;
import org.eclipse.jetty.http.PreEncodedHttpField;
import org.eclipse.jetty.server.Request;
import org.eclipse.jetty.server.Server;
import org.eclipse.jetty.server.handler.AbstractHandler;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.concurrent.atomic.AtomicLong;

/** Replicates the same happy path as the Dropwizard getting started example without
 *  and configuration builtin
 */
public class RawJetty {
    private static final String defaultName = "Nick" ;
    private static final String template = "Hello %s!";
    private static final JsonFactory jsonFactory = new JsonFactory();
    private static final AtomicLong counter = new AtomicLong();

    public static void main( String[] args ) throws Exception {
        Server server = new Server(8095);
        server.setHandler(new DropwizardExampleHandler());
        server.start();
        server.join();
    }

    public static class DropwizardExampleHandler extends AbstractHandler {
        private static final HttpField contentType = new PreEncodedHttpField(HttpHeader.CONTENT_TYPE, "application/json");

        @Override
        public void handle(String s, Request baseRequest, HttpServletRequest request, HttpServletResponse response)
                throws IOException, ServletException {
            baseRequest.setHandled(true);
            final String name = Strings.nullToEmpty(request.getParameter("name"));
            baseRequest.getResponse().getHttpFields().add(contentType);

            if (name.length() > 5) {
                response.setStatus(HttpServletResponse.SC_BAD_REQUEST);
                try (final JsonGenerator json = jsonFactory.createGenerator(response.getOutputStream())) {
                    json.writeStartObject();
                    json.writeStringField("error", "Query parameter name must be shorter than 5 letters");
                    json.writeEndObject();
                    return;
                }
            }

            response.setStatus(HttpServletResponse.SC_OK);
            try (final JsonGenerator json = jsonFactory.createGenerator(response.getOutputStream())) {
                json.writeStartObject();
                json.writeNumberField("id", counter.incrementAndGet());
                json.writeStringField("content", String.format(template, name.length() != 0 ? name : defaultName));
                json.writeEndObject();
            }
        }
    }
}