OkHttp3Stack volley

package com.yong.volleyok.okhttp;
	import com.android.volley.AuthFailureError;
	import com.android.volley.Request;
	import com.android.volley.toolbox.HttpStack;
	import org.apache.http.HttpEntity;
	import org.apache.http.HttpResponse;
	import org.apache.http.ProtocolVersion;
	import org.apache.http.StatusLine;
	import org.apache.http.entity.BasicHttpEntity;
	import org.apache.http.message.BasicHeader;
	import org.apache.http.message.BasicHttpResponse;
	import org.apache.http.message.BasicStatusLine;
	import java.io.IOException;
	import java.util.Map;
	import java.util.concurrent.TimeUnit;
	import okhttp3.Headers;
	import okhttp3.MediaType;
	import okhttp3.OkHttpClient;
	import okhttp3.Protocol;
	import okhttp3.RequestBody;
	import okhttp3.Response;
	import okhttp3.ResponseBody;
	/**
	* <b>Project:</b> com.yong.volleyok <br>
	* <b>Create Date:</b> 2016/4/22 <br>
	* <b>Author:</b> qingyong <br>
	* <b>Description:</b> 使用OkHttp作为Volley的请求的实现 <br>
	*/
	public class OkHttp3Stack implements HttpStack {
	private final OkHttpClient mClient;
	public OkHttp3Stack(OkHttpClient client) {
	this.mClient = client;
	}
	private static HttpEntity entityFromOkHttpResponse(Response response) throws IOException {
	BasicHttpEntity entity = new BasicHttpEntity();
	ResponseBody body = response.body();
	entity.setContent(body.byteStream());
	entity.setContentLength(body.contentLength());
	entity.setContentEncoding(response.header("Content-Encoding"));
	if (body.contentType() != null) {
	entity.setContentType(body.contentType().type());
	}
	return entity;
	}
	@SuppressWarnings("deprecation")
	private static void setConnectionParametersForRequest
	(okhttp3.Request.Builder builder, Request<?> request)
	throws IOException, AuthFailureError {
	switch (request.getMethod()) {
	case Request.Method.DEPRECATED_GET_OR_POST:
	byte[] postBody = request.getPostBody();
	if (postBody != null) {
	builder.post(RequestBody.create
	(MediaType.parse(request.getPostBodyContentType()), postBody));
	}
	break;
	case Request.Method.GET:
	builder.get();
	break;
	case Request.Method.DELETE:
	builder.delete();
	break;
	case Request.Method.POST:
	builder.post(createRequestBody(request));
	break;
	case Request.Method.PUT:
	builder.put(createRequestBody(request));
	break;
	case Request.Method.HEAD:
	builder.head();
	break;
	case Request.Method.OPTIONS:
	builder.method("OPTIONS", null);
	break;
	case Request.Method.TRACE:
	builder.method("TRACE", null);
	break;
	case Request.Method.PATCH:
	builder.patch(createRequestBody(request));
	break;
	default:
	throw new IllegalStateException("Unknown method type.");
	}
	}
	private static RequestBody createRequestBody(Request request) throws AuthFailureError {
	final byte[] body = request.getBody();
	if (body == null) return null;
	return RequestBody.create(MediaType.parse(request.getBodyContentType()), body);
	}
	private static ProtocolVersion parseProtocol(final Protocol protocol) {
	switch (protocol) {
	case HTTP_1_0:
	return new ProtocolVersion("HTTP", 1, 0);
	case HTTP_1_1:
	return new ProtocolVersion("HTTP", 1, 1);
	case SPDY_3:
	return new ProtocolVersion("SPDY", 3, 1);
	case HTTP_2:
	return new ProtocolVersion("HTTP", 2, 0);
	}
	throw new IllegalAccessError("Unkwown protocol");
	}
	@Override
	public HttpResponse performRequest(Request<?> request, Map<String, String> additionalHeaders)
	throws IOException, AuthFailureError {
	int timeoutMs = request.getTimeoutMs();
	OkHttpClient client = mClient.newBuilder()
	.readTimeout(timeoutMs, TimeUnit.MILLISECONDS)
	.connectTimeout(timeoutMs, TimeUnit.MILLISECONDS)
	.writeTimeout(timeoutMs, TimeUnit.MILLISECONDS)
	.build();
	// 请求构造器
	okhttp3.Request.Builder okHttpRequestBuilder = new okhttp3.Request.Builder();
	Map<String, String> headers = request.getHeaders();
	for (final String name : headers.keySet()) {
	okHttpRequestBuilder.addHeader(name, headers.get(name));
	}
	for (final String name : additionalHeaders.keySet()) {
	okHttpRequestBuilder.addHeader(name, additionalHeaders.get(name));
	}
	setConnectionParametersForRequest(okHttpRequestBuilder, request);
	// 请求
	okhttp3.Request okhttp3Request = okHttpRequestBuilder.
	url(request.getUrl()).
	build();
	// 响应
	Response okHttpResponse = client.newCall(okhttp3Request).execute();
	StatusLine responseStatus = new BasicStatusLine
	(
	parseProtocol(okHttpResponse.protocol()),
	okHttpResponse.code(),
	okHttpResponse.message()
	);
	BasicHttpResponse response = new BasicHttpResponse(responseStatus);
	response.setEntity(entityFromOkHttpResponse(okHttpResponse));
	Headers responseHeaders = okHttpResponse.headers();
	for (int i = 0, len = responseHeaders.size(); i < len; i++) {
	final String name = responseHeaders.name(i), value = responseHeaders.value(i);
	if (name != null) {
	response.addHeader(new BasicHeader(name, value));
	}
	}
	return response;
	}
	}