HttpURLConnection的get和post处理方法（含图片）

原文地址http://blog.csdn.net/arsenic/article/details/8120581

通用方法GET和POST

[java] view
plaincop

package com.dong.test.binaryimage;

import java.io.BufferedReader;

import java.io.ByteArrayOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.io.UnsupportedEncodingException;

import java.net.HttpURLConnection;

import java.net.MalformedURLException;

import java.net.URL;

import java.net.URLConnection;

import java.net.URLEncoder;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

public class TestHttpPost {

private static String PATH = "http://localhost:8080/TestWeb/servlet/HelloServer";

private static URL url;

public TestHttpPost() {

// TODO Auto-generated constructor stub

}

static {

try {

url = new URL(PATH);

} catch (MalformedURLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

/**

* @param args

*/

public static void main(String[] args) {

Map<String, String> map = new HashMap<String, String>();

map.put("name", "xiaowang");

map.put("age", "29");

System.out.println(sendPostMessage(map, "UTF-8"));

System.out.println(sendGet(PATH,"name=xiaowang"));

}

public static String sendGet(String url, String param)

{

String result = "";

BufferedReader in = null;

try

{

String urlName = url + "?" + param;

URL realUrl = new URL(urlName);

// 打开和URL之间的连接

URLConnection conn = realUrl.openConnection();

// 设置通用的请求属性

conn.setRequestProperty("accept", "*/*");

conn.setRequestProperty("connection", "Keep-Alive");

conn.setRequestProperty("user-agent",

"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)");

// 建立实际的连接

conn.connect();

// 获取所有响应头字段

Map<String, List<String>> map = conn.getHeaderFields();

// 遍历所有的响应头字段

for (String key : map.keySet())

{

System.out.println(key + "--->" + map.get(key));

}

// 定义BufferedReader输入流来读取URL的响应

in = new BufferedReader(

new InputStreamReader(conn.getInputStream()));

String line;

while ((line = in.readLine()) != null)

{

result += "\n" + line;

}

}

catch (Exception e)

{

System.out.println("发送GET请求出现异常！" + e);

e.printStackTrace();

}

// 使用finally块来关闭输入流

finally

{

try

{

if (in != null)

{

in.close();

}

}

catch (IOException ex)

{

ex.printStackTrace();

}

}

return result;

}

public static String sendPostMessage(Map<String, String> params,

String encode) {

// 作为StringBuffer初始化的字符串

StringBuffer buffer = new StringBuffer();

try {

if (params != null && !params.isEmpty()) {

for (Map.Entry<String, String> entry : params.entrySet()) {

// 完成转码操作

buffer.append(entry.getKey()).append("=").append(

URLEncoder.encode(entry.getValue(), encode))

.append("&");

}

buffer.deleteCharAt(buffer.length() - 1);

}

// System.out.println(buffer.toString());

// 删除掉最有一个&

System.out.println("-->>" + buffer.toString());

HttpURLConnection urlConnection = (HttpURLConnection) url

.openConnection();

urlConnection.setConnectTimeout(3000);

urlConnection.setRequestMethod("POST");

urlConnection.setDoInput(true);// 表示从服务器获取数据

urlConnection.setDoOutput(true);// 表示向服务器写数据

// 获得上传信息的字节大小以及长度

byte[] mydata = buffer.toString().getBytes();

// 表示设置请求体的类型是文本类型

urlConnection.setRequestProperty("Content-Type",

"application/x-www-form-urlencoded");

urlConnection.setRequestProperty("Content-Length", String

.valueOf(mydata.length));

// 获得输出流,向服务器输出数据

OutputStream outputStream = urlConnection.getOutputStream();

outputStream.write(mydata, 0, mydata.length);

outputStream.close();

// 获得服务器响应的结果和状态码

int responseCode = urlConnection.getResponseCode();

if (responseCode == 200) {

return changeInputStream(urlConnection.getInputStream(), encode);

}

} catch (UnsupportedEncodingException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return "";

}

private static String changeInputStream(InputStream inputStream,

String encode) {

// TODO Auto-generated method stub

ByteArrayOutputStream outputStream = new ByteArrayOutputStream();

byte[] data = new byte[1024];

int len = 0;

String result = "";

if (inputStream != null) {

try {

while ((len = inputStream.read(data)) != -1) {

outputStream.write(data, 0, len);

}

result = new String(outputStream.toByteArray(), encode);

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

return result;

}

}

GET处理方法

[java] view
plaincopy

package com.http.get;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.net.HttpURLConnection;

import java.net.MalformedURLException;

import java.net.URL;

import org.apache.http.message.BasicNameValuePair;

public class HttpUtils {

private static String URL_PATH = "http://192.168.0.102:8080/myhttp/pro1.png";

public HttpUtils() {

// TODO Auto-generated constructor stub

}

public static void saveImageToDisk() {

InputStream inputStream = getInputStream();

byte[] data = new byte[1024];

int len = 0;

FileOutputStream fileOutputStream = null;

try {

fileOutputStream = new FileOutputStream("C:\\test.png");

while ((len = inputStream.read(data)) != -1) {

fileOutputStream.write(data, 0, len);

}

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} finally {

if (inputStream != null) {

try {

inputStream.close();

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

if (fileOutputStream != null) {

try {

fileOutputStream.close();

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

}

}

/**

* 获得服务器端的数据,以InputStream形式返回

* @return

*/

public static InputStream getInputStream() {

InputStream inputStream = null;

HttpURLConnection httpURLConnection = null;

try {

URL url = new URL(URL_PATH);

if (url != null) {

httpURLConnection = (HttpURLConnection) url.openConnection();

// 设置连接网络的超时时间

httpURLConnection.setConnectTimeout(3000);

httpURLConnection.setDoInput(true);

// 表示设置本次http请求使用GET方式请求

httpURLConnection.setRequestMethod("GET");

int responseCode = httpURLConnection.getResponseCode();

if (responseCode == 200) {

// 从服务器获得一个输入流

inputStream = httpURLConnection.getInputStream();

}

}

} catch (MalformedURLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return inputStream;

}

public static void main(String[] args) {

// 从服务器获得图片保存到本地

saveImageToDisk();

}

}

POST

[java] view
plaincopy

package com.http.post;

import java.io.ByteArrayOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.io.UnsupportedEncodingException;

import java.net.HttpURLConnection;

import java.net.MalformedURLException;

import java.net.URL;

import java.net.URLEncoder;

import java.util.HashMap;

import java.util.Map;

public class HttpUtils {

// 请求服务器端的url

private static String PATH = "http://192.168.0.102:8080/myhttp/servlet/LoginAction";

private static URL url;

public HttpUtils() {

// TODO Auto-generated constructor stub

}

static {

try {

url = new URL(PATH);

} catch (MalformedURLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

/**

* @param params

* 填写的url的参数

* @param encode

* 字节编码

* @return

*/

public static String sendPostMessage(Map<String, String> params,

String encode) {

// 作为StringBuffer初始化的字符串

StringBuffer buffer = new StringBuffer();

try {

if (params != null && !params.isEmpty()) {

for (Map.Entry<String, String> entry : params.entrySet()) {

// 完成转码操作

buffer.append(entry.getKey()).append("=").append(

URLEncoder.encode(entry.getValue(), encode))

.append("&");

}

buffer.deleteCharAt(buffer.length() - 1);

}

// System.out.println(buffer.toString());

// 删除掉最有一个&

System.out.println("-->>"+buffer.toString());

HttpURLConnection urlConnection = (HttpURLConnection) url

.openConnection();

urlConnection.setConnectTimeout(3000);

urlConnection.setRequestMethod("POST");

urlConnection.setDoInput(true);// 表示从服务器获取数据

urlConnection.setDoOutput(true);// 表示向服务器写数据

// 获得上传信息的字节大小以及长度

byte[] mydata = buffer.toString().getBytes();

// 表示设置请求体的类型是文本类型

urlConnection.setRequestProperty("Content-Type",

"application/x-www-form-urlencoded");

urlConnection.setRequestProperty("Content-Length",

String.valueOf(mydata.length));

// 获得输出流,向服务器输出数据

OutputStream outputStream = urlConnection.getOutputStream();

outputStream.write(mydata,0,mydata.length);

outputStream.close();

// 获得服务器响应的结果和状态码

int responseCode = urlConnection.getResponseCode();

if (responseCode == 200) {

return changeInputStream(urlConnection.getInputStream(), encode);

}

} catch (UnsupportedEncodingException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return "";

}

/**

* 将一个输入流转换成指定编码的字符串

*

* @param inputStream

* @param encode

* @return

*/

private static String changeInputStream(InputStream inputStream,

String encode) {

// TODO Auto-generated method stub

ByteArrayOutputStream outputStream = new ByteArrayOutputStream();

byte[] data = new byte[1024];

int len = 0;

String result = "";

if (inputStream != null) {

try {

while ((len = inputStream.read(data)) != -1) {

outputStream.write(data, 0, len);

}

result = new String(outputStream.toByteArray(), encode);

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

return result;

}

/**

* @param args

*/

public static void main(String[] args) {

// TODO Auto-generated method stub

Map<String, String> params = new HashMap<String, String>();

params.put("username", "admin");

params.put("password", "1234");

String result = HttpUtils.sendPostMessage(params, "utf-8");

System.out.println("--result->>" + result);

}

}

[java] view
plaincopy

package com.http.post;

import java.io.ByteArrayOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.UnsupportedEncodingException;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

import org.apache.http.HttpResponse;

import org.apache.http.NameValuePair;

import org.apache.http.client.ClientProtocolException;

import org.apache.http.client.entity.UrlEncodedFormEntity;

import org.apache.http.client.methods.HttpPost;

import org.apache.http.impl.client.DefaultHttpClient;

import org.apache.http.message.BasicNameValuePair;

public class HttpUtils {

public HttpUtils() {

// TODO Auto-generated constructor stub

}

public static String sendHttpClientPost(String path,

Map<String, String> map, String encode) {

List<NameValuePair> list = new ArrayList<NameValuePair>();

if (map != null && !map.isEmpty()) {

for (Map.Entry<String, String> entry : map.entrySet()) {

list.add(new BasicNameValuePair(entry.getKey(), entry

.getValue()));

}

}

try {

// 实现将请求的参数封装到表单中,请求体重

UrlEncodedFormEntity entity = new UrlEncodedFormEntity(list, encode);

// 使用Post方式提交数据

HttpPost httpPost = new HttpPost(path);

httpPost.setEntity(entity);

// 指定post请求

DefaultHttpClient client = new DefaultHttpClient();

HttpResponse httpResponse = client.execute(httpPost);

if (httpResponse.getStatusLine().getStatusCode() == 200) {

return changeInputStream(httpResponse.getEntity().getContent(),

encode);

}

} catch (UnsupportedEncodingException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (ClientProtocolException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return "";

}

/**

* 将一个输入流转换成指定编码的字符串

*

* @param inputStream

* @param encode

* @return

*/

public static String changeInputStream(InputStream inputStream,

String encode) {

// TODO Auto-generated method stub

ByteArrayOutputStream outputStream = new ByteArrayOutputStream();

byte[] data = new byte[1024];

int len = 0;

String result = "";

if (inputStream != null) {

try {

while ((len = inputStream.read(data)) != -1) {

outputStream.write(data, 0, len);

}

result = new String(outputStream.toByteArray(), encode);

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

return result;

}

/**

* @param args

*/

public static void main(String[] args) {

// TODO Auto-generated method stub

String path = "http://192.168.0.102:8080/myhttp/servlet/LoginAction";

Map<String, String> params = new HashMap<String, String>();

params.put("username", "admin");

params.put("password", "123");

String result = HttpUtils.sendHttpClientPost(path, params, "utf-8");

System.out.println("-->>"+result);

}

}