zhttp是一个封装了httpcomponents的工具，用于简化httpcomponents的操作。

用httpcomponents发送一个get请求，至少需要这样：

CloseableHttpClient httpClient = HttpClients.createDefault();
HttpGet httpGet = new HttpGet(url);

// Create a custom response handler
ResponseHandler<String> responseHandler = new ResponseHandler<String>() {

	private HttpResponse response;

	@Override
	public String handleResponse(final HttpResponse response) throws IOException {
		this.response = response;
		int status = response.getStatusLine().getStatusCode();
		if (status >= 200 && status < 300) {
			HttpEntity entity = response.getEntity();
			return entity != null ? EntityUtils.toString(entity, "UTF-8") : null;
		} else {
			throw new ClientProtocolException("Unexpected response status: " + status);
		}
	}

};
String responseBody;
try {
	responseBody = httpClient.execute(httpGet, responseHandler);
} catch (IOException e) {
	throw new HttpUtilsException("Get from " + url + " error.", e);
} finally {
	httpClient.close();
}

用zhttp封装后，现在发送一个get请求，只需要以下几步：

BasicHttpUtils basicHttpUtils = new BasicHttpUtils(String.class, url);

String responseBody;
try {
	responseBody = (String) basicHttpUtils.get();
} catch (HttpUtilsException e) {
	throw new ServiceException("Get from " + url + " error.", e);
} catch (IOException e) {
	throw new ServiceException("Get from " + url + " error.", e);
}

zhttp还提供了发送post请求、下载文件、发送带Authorization Header的HTTP请求、在请求体中带上表单数据、在请求体中带上文本或json数据等功能。

下面我们介绍zhttp的使用。

一、在项目中引用zhttp；

1.1 下载“zjson-1.7.jar”到本地（下载地址：https://github.com/junior9919/zjson/releases/download/1.7/zjson-1.7.jar）；

1.2 用命令将zjson安装到本地maven仓库；

mvn install:install-file -Dfile=D:\idea-workspace\zjson\target\zjson-1.7.jar -DgroupId=com.halo -DartifactId=zjson -Dversion=1.7 -Dpackaging=jar

1.3 在pom.xml文件中加入引用（在build-pluginManagement-plugins小节，如果已有maven-install-plugin就不需要再加了）：

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-install-plugin</artifactId>
    <version>2.5.2</version>
</plugin>

1.4 在pom.xml文件中加入以下依赖（在dependencies小节）：

<!-- json-lib and utils dependencies -->
<dependency>
    <groupId>net.sf.json-lib</groupId>
    <artifactId>json-lib</artifactId>
    <version>2.4</version>
    <classifier>jdk15</classifier>
</dependency>

<dependency>
    <groupId>com.halo</groupId>
    <artifactId>zjson</artifactId>
    <version>1.7</version>
</dependency>
<!-- json-lib and utils dependencies -->

1.5 下载zhttp-2.3.jar到本地（下载地址：https://github.com/junior9919/zhttp/releases/download/2.3/zhttp-2.3.jar）；

1.6 用以下命令将zhttp安装到本地maven仓库；

mvn install:install-file -Dfile=D:\idea-workspace\zhttp\target\zhttp-2.3.jar -DgroupId=com.halo -DartifactId=zhttp -Dversion=2.3 -Dpackaging=jar

1.7 在pom.xml文件中加入以下依赖（在dependencies小节）：

<!-- http client and utils dependencies -->
<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpcore</artifactId>
    <version>4.4.10</version>
</dependency>

<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpclient</artifactId>
    <version>4.5.6</version>
</dependency>

<dependency>
    <groupId>com.halo</groupId>
    <artifactId>zhttp</artifactId>
    <version>2.3</version>
</dependency>
<!-- http client and utils dependencies -->

二、zhttp的使用；

2.1 最简单的GET请求上面已经介绍过，现在来看看URL后带参数的get请求：

BasicHttpUtils basicHttpUtils = new BasicHttpUtils(String.class, url);

Map<String, String> args = new HashMap<>();
args.put("account", account);
args.put("accessToken", accessToken);
args.put("client", "h5");

basicHttpUtils.setArgs(args);

String responseBody;
try {
    responseBody = (String) basicHttpUtils.get();
} catch (HttpUtilsException e) {
    throw new ServiceException("Get from " + url + " error.", e);
} catch (IOException e) {
    throw new ServiceException("Get from " + url + " error.", e);
}

2.2 POST请求，将上面的“get”换成“post”即可：

BasicHttpUtils basicHttpUtils = new BasicHttpUtils(String.class, url);

Map<String, String> args = new HashMap<>();
args.put("account", account);
args.put("accessToken", accessToken);
args.put("client", "h5");

basicHttpUtils.setArgs(args);

String responseBody;
try {
    responseBody = (String) basicHttpUtils.post();
} catch (HttpUtilsException e) {
    throw new ServiceException("Post from " + url + " error.", e);
} catch (IOException e) {
    throw new ServiceException("Post from " + url + " error.", e);
}

2.3 HTTP表单里带数据的POST请求：

BasicHttpUtils basicHttpUtils = new BasicHttpUtils(String.class, url);

AssemblyLine assemblyLine = basicHttpUtils.getAssemblyLine();
if (null == assemblyLine) {
    assemblyLine = new AssemblyLine();
    basicHttpUtils.setAssemblyLine(assemblyLine);
}

List<BasicNameValuePair> formData = new ArrayList<>();
formData.add(new BasicNameValuePair("grant_type", "authorization_code"));
formData.add(new BasicNameValuePair("code", code));
formData.add(new BasicNameValuePair("redirect_uri", redirectUrl));

FormDataAssembler formDataAssembler = new FormDataAssembler(formData);
assemblyLine.addAssembler(formDataAssembler);

String responseBody;
try {
    responseBody = (String) basicHttpUtils.post();
} catch (HttpUtilsException e) {
    throw new ServiceException("Post from " + url + " error.", e);
} catch (IOException e) {
    throw new ServiceException("Post from " + url + " error.", e);
}

2.4 在请求体中带上文本或json数据的POST请求：

BasicHttpUtils basicHttpUtils = new BasicHttpUtils(String.class, url);

AssemblyLine assemblyLine = basicHttpUtils.getAssemblyLine();
if (null == assemblyLine) {
    assemblyLine = new AssemblyLine();
    basicHttpUtils.setAssemblyLine(assemblyLine);
}

RequestBodyAssembler requestBodyAssembler = new RequestBodyAssembler("{ "id": 1 }", "application/json");
assemblyLine.addAssembler(formDataAssembler);

String responseBody;
try {
    responseBody = (String) basicHttpUtils.post();
} catch (HttpUtilsException e) {
    throw new ServiceException("Post from " + url + " error.", e);
} catch (IOException e) {
    throw new ServiceException("Post from " + url + " error.", e);
}

2.5 带Authorization Header的HTTP请求，目前只实现了Basic验证：

BasicHttpUtils basicHttpUtils = new BasicHttpUtils(String.class, url);

AssemblyLine assemblyLine = basicHttpUtils.getAssemblyLine();
if (null == assemblyLine) {
    assemblyLine = new AssemblyLine();
    basicHttpUtils.setAssemblyLine(assemblyLine);
}

String clientId = "25841d1961f25b427fc8";
String clientSecret = "fd57902b2fb7243f524814ab640361";
AuthorizationHeaderAssembler authorizationHeaderAssembler =
        new AuthorizationHeaderAssembler(clientId, clientSecret, AuthorizationType.Basic);
assemblyLine.addAssembler(authorizationHeaderAssembler);

String responseBody;
try {
    responseBody = (String) basicHttpUtils.post();
} catch (HttpUtilsException e) {
    throw new ServiceException("Post from " + url + " error.", e);
} catch (IOException e) {
    throw new ServiceException("Post from " + url + " error.", e);
}

2.6 使用“AdvanceHttpUtils”，可以将Java对象（POJO对象）转化成json，并将返回结果的json转化成Java对象：

AdvanceHttpUtils advanceHttpUtils = new AdvanceHttpUtils(url);

advanceHttpUtils.setRequestJsonUtils(new JSONUtils(AccessTokenRequestBean.class));

AccessTokenRequestBean accessTokenRequestBean = new AccessTokenRequestBean();
accessTokenRequestBean.setUserId(userId);
accessTokenRequestBean.setPassword(password);
advanceHttpUtils.setRequestJsonBean(accessTokenRequestBean);

advanceHttpUtils.setResponseJsonUtils(new JSONUtils(AccessTokenResponseBean.class));

AccessTokenResponseBean accessTokenResponseBean;
try {
    accessTokenResponseBean = (AccessTokenResponseBean) advanceHttpUtils.post();
} catch (HttpUtilsException e) {
    throw new ServiceException("Get login access token error.", e);
} catch (IOException e) {
    throw new ServiceException("Get login access token error.", e);
}

2.7 下载文件：

BasicHttpUtils basicHttpUtils = new BasicHttpUtils<>(File.class, url);
File downloadFile = null;
try {
    downloadFile = (File) basicHttpUtils.get();
} catch (HttpUtilsException e) {
    e.printStackTrace();
} catch (IOException e) {
    e.printStackTrace();
}

System.out.println(downloadFile.getAbsolutePath());