OutputStream 输出流，用来write写的，把数据写进入
如果是文件输出流，结果就是把数据写入文件
如果是HttpURLConnection输出流，结果就是把数据写入http发送数据
InputStream 输入流，用来read读取的，把数据读出来
如果是文件输入流，结果就是把数据从文件中读取到字节、字符数组中
如果是HttpURLConnection输入流，结果就是读取数据接收http数据
字符流（一次可以处理一个缓冲区）一次操作比字节流（一次一个字节）效率高。
字节流通常用于处理二进制数据，不支持直接读写字符；字符流通常用于处理文本数据
在读写文件需要对文本内容进行处理：按行处理、比较特定字符的时候一般会选择字符流；仅仅读写文件，不处理内容，一般选择字节流
https://ww.cnblogs.com/liangbaolong/p/12880487.html
从目标文件或资源读取
URL u = new URL(url);
UrlResource ur = new UrlResource(u);
输入读：
InputStream in = ur.getInputStream(); //字节输入流 例如从url资源获取
FileInputStream in = new FileInputStream(new File("D:/test.txt")); 文件输入流（字节流）
FileReader fr = new FileReader(new File("D:/test.txt")); 文件输入流（字符流）
InputStreamReader isr = new InputStreamReader(in,"gbk"); 字符输入流
Reader read = new BufferedReader(isr); 字符输入流
输出写：
OutputStream outStream = response.getOutputStream(); 字节输出流 例如从http响应获取
ByteArrayOutputStream bao = new ByteArrayOutputStream(); 字节输出流
FileOutputStream fos = new FileOutputStream(file); 文件输出流 （字节流）
FileWriter fw = new FileWriter(new File("D:/test2.txt")); 文件输出流 （字符流）
OutputStreamWriter out = new OutputStreamWriter(fos); 字符输出流
Writer wr = new BufferedWriter(out); 字符输出流
字节流：
while((i=in.read(b))>=0){//从输入流读取到字节数组 i是返回的读到b的字节个数 返回-1表示已读完
bao.write(b);//字节数组写入输出流
b = new byte[1024];
}
字符流：
while((c= read.read(ch))>=0){ //从输入流读取字符数组
//out.write(ch,0, c); //字符数组写入输出流
wr.write(ch);
ch = new char[5];
}
wr.flush();
wr.close();
操作字符流涉及字符编码，字节流不涉及
基于字节流的stream：
DataOutputStream----DataInputStream:
FileOutputStream-----FileInputStream:
基于字符流的stream（典型的以write和reader来标识的）：
FileWriter---FileReader:
StringWriter---StringReader:
BufferedWriter--BufferedReader
https服务器搭建
https://pay.weixin.qq.com/wiki/doc/api/wxpay_v2/papay/chapter2_7.shtml
public static void main(String[] args) {
//传入null请求接收方会报错
String s1 = httpReq("http://localhost:9098/insurance/insuranceAward/insuranceSport2.json?userId=123&policyNo=321","123xxxxxxmmmmmmm");
System.out.println("result:"+s1);
}
@RequestMapping(value = "/insuranceSport2")
@ResponseBody
public ResultVO<String> test2(@Valid MyRequest request, HttpServletRequest req, HttpServletResponse res,@RequestBody String jsonString) {
ResultVO rs = new ResultVO();
System.out.println(request);
System.out.println(jsonString);
return rs;
}
public static String httpReq(String url, String params) {
StringBuffer bufferRes = new StringBuffer();
HttpURLConnection conn = null;
InputStream in = null;
try {
URL realUrl = new URL(url);
conn = (HttpURLConnection) realUrl
.openConnection();
// 连接超时
conn.setConnectTimeout(30000);
// 读取超时 --服务器响应比较慢,增大时间
conn.setReadTimeout(30000);
HttpURLConnection.setFollowRedirects(true);
// 请求方式
conn.setRequestMethod("GET");
conn.setDoOutput(true);
conn.setDoInput(true);
conn.setUseCaches(false);
if (StringUtils.isNotBlank(params)) {
conn.setRequestProperty("CONTENT_LENGTH","" + params.length());
}
// conn.setRequestProperty("Accept-Charset", "UTF-8");
conn.setRequestProperty("User-Agent",
"Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20100101 Firefox/21.0");
conn.setRequestProperty("Referer", "https://api.weixin.qq.com/");
// 发送请求参数
if (params != null) {
OutputStream out = conn.getOutputStream();
out.write(params.getBytes("UTF-8"));
out.flush();
out.close();
out = null;
}
//接收返回
public static void main(String[] args) {
//传入null请求接收方会报错
String s1 = httpReq("http://localhost:9098/insurance/insuranceAward/insuranceSport2.json?userId=123&policyNo=321","123xxxxxxmmmmmmm");
System.out.println("result:"+s1);
}
@RequestMapping(value = "/insuranceSport2")
@ResponseBody
public ResultVO<String> test2(@Valid MyRequest request, HttpServletRequest req, HttpServletResponse res,@RequestBody String jsonString) {
ResultVO rs = new ResultVO();
System.out.println(request);
System.out.println(jsonString);
return rs;
}
public static String httpReq(String url, String params) {
StringBuffer bufferRes = new StringBuffer();
HttpURLConnection conn = null;
InputStream in = null;
try {
URL realUrl = new URL(url);
conn = (HttpURLConnection) realUrl
.openConnection();
// 连接超时
conn.setConnectTimeout(30000);
// 读取超时 --服务器响应比较慢,增大时间
conn.setReadTimeout(30000);
HttpURLConnection.setFollowRedirects(true);
// 请求方式
conn.setRequestMethod("GET");
conn.setDoOutput(true);
conn.setDoInput(true);
conn.setUseCaches(false);
if (StringUtils.isNotBlank(params)) {
conn.setRequestProperty("CONTENT_LENGTH","" + params.length());
}
// conn.setRequestProperty("Accept-Charset", "UTF-8");
conn.setRequestProperty("User-Agent",
"Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20100101 Firefox/21.0");
conn.setRequestProperty("Referer", "https://api.weixin.qq.com/");
// 发送请求参数
if (params != null) {
OutputStream out = conn.getOutputStream();
out.write(params.getBytes("UTF-8"));
out.flush();
out.close();
out = null;
}
//接收返回
in = conn.getInputStream();
BufferedReader read = new BufferedReader(new InputStreamReader(in,"UTF-8"));
String valueString = null;
while ((valueString = read.readLine()) != null) {
bufferRes.append(valueString);
}
in.close();
read.close();
in = null;
read = null;
if (conn != null) {
conn.disconnect();
}
} catch (Exception e) {
LOGGER.error("http请求微信服务异常", e);
} finally{
conn = null;
in = null;
}
return bufferRes.toString();
} in = conn.getInputStream();
BufferedReader read = new BufferedReader(new InputStreamReader(in,"UTF-8"));
String valueString = null;
while ((valueString = read.readLine()) != null) {
bufferRes.append(valueString);
}
in.close();
read.close();
in = null;
read = null;
if (conn != null) {
conn.disconnect();
}
} catch (Exception e) {
LOGGER.error("http请求微信服务异常", e);
} finally{
conn = null;
in = null;
}
return bufferRes.toString();
}
// https
public static String httpRequest(String requestUrl, String outputStr) {
StringBuffer buffer = new StringBuffer();
try {
TrustManager[] tm = { new TrustAnyTrustManager() };
SSLContext sslContext = SSLContext.getInstance("SSL", "SunJSSE");
sslContext.init(null, tm, new java.security.SecureRandom());
SSLSocketFactory ssf = sslContext.getSocketFactory();
URL url = new URL(requestUrl);
HttpsURLConnection httpUrlConn = (HttpsURLConnection) url
.openConnection();
httpUrlConn.setSSLSocketFactory(ssf);
httpUrlConn.setDoOutput(true);
httpUrlConn.setDoInput(true);
httpUrlConn.setUseCaches(false);
// 设置请求方式（GET/POST）
httpUrlConn.setRequestMethod("POST");
if (null != outputStr) {
OutputStream outputStream = httpUrlConn.getOutputStream();
// 注意编码格式，防止中文乱码
outputStream.write(outputStr.getBytes("UTF-8"));
outputStream.close();
}
// 将返回的输入流转换成字符串
InputStream inputStream = httpUrlConn.getInputStream();
InputStreamReader inputStreamReader = new InputStreamReader(
inputStream, "UTF-8");
BufferedReader bufferedReader = new BufferedReader(
inputStreamReader);
String str = null;
while ((str = bufferedReader.readLine()) != null) {
buffer.append(str);
}
bufferedReader.close();
inputStreamReader.close();
// 释放资源
inputStream.close();
inputStream = null;
httpUrlConn.disconnect();
return buffer.toString();
} catch (Exception e) {
LOGGER.error("WeixinHttpUtil-->httpRequest error"+e.getMessage(),e);
}
return "";
}
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