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Category Archives: Programming Language

利用404特性同步文件(.NET版)

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public partial class _404 : System.Web.UI.Page
{
/// <summary>
/// 目标服务器URL
/// </summary>
private readonly string targetUrl = "目标服务器";
 
protected void Page_Load(object sender, EventArgs e)
{
var folderPath = "";
 
try
{
// PrintSeverVariables();
 
// 取出资源地址
var fullUrl = Request.ServerVariables["QUERY_STRING"]; // 全地址
var resourceUrl = Regex.Replace(fullUrl, @"404;https?\://[^/]+", "");
 
// 取出文件名
var lastMatch = Regex.Match(resourceUrl, @"[^/]+(?!.*\.xlsx?)");
if (!lastMatch.Success || lastMatch.Groups.Count < 1)
{
Response.StatusCode = 404;
return;
}
 
var fileName = lastMatch.Groups[0].Value.Split('?')[0];
if (string.IsNullOrEmpty(fileName) || fileName.IndexOf('.') < 0)
{
Response.StatusCode = 404;
return;
}
 
// 扩展名
var extensionName = fileName.Split('.')[1].ToLower();
if (extensionName != "xls" && extensionName != "xlsx") // 只拉取excel文件
{
Response.StatusCode = 404;
return;
}
 
// 拉取文件 并保存
using (var stream = Get(targetUrl + resourceUrl))
{
// 创建文件夹
folderPath = Server.MapPath(resourceUrl.Replace(fileName, "").Replace("/jq", ""));
if (!Directory.Exists(folderPath))
{
Directory.CreateDirectory(folderPath);
}
 
// 保存文件
SaveFile(stream, folderPath + fileName);
}
 
// 转向拉取的静态资源
Response.ContentType = "application/octet-stream";
Response.WriteFile(folderPath + fileName);
}
catch (Exception ex)
{
Response.StatusCode = 404;
return;
}
}
 
/// <summary>
/// 保存文件
/// </summary>
/// <param name="stream"></param>
/// <param name="fileName"></param>
public void SaveFile(Stream stream, string fileName)
{
// 保存文件
using (var fs = new FileStream(fileName, FileMode.OpenOrCreate))
{
stream.CopyTo(fs);
 
fs.Close();
stream.Close();
}
}
 
/// <summary>
/// Get请求
/// </summary>
/// <param name="url"></param>
/// <param name="postData"></param>
/// <returns></returns>
static Stream Get(string url)
{
//请求
var request = (HttpWebRequest)WebRequest.Create(url);
request.Timeout = 600000; // 600秒
request.Method = "GET";
 
//接收
var response = (HttpWebResponse)request.GetResponse();
return response.GetResponseStream();
}
 
 
/// <summary>
/// 打印环境变量
/// </summary>
void PrintSeverVariables()
{
foreach (string key in Request.ServerVariables)
{
Response.Write("<b>" + key + ":</b>" + Request.ServerVariables[key] + "<br>");
}
}
}

 

龙生   17 Aug 2021
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Asp.Net中强制文件下载

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public HttpResponseMessage ImportTemplate(string fileName)
{
var context = HttpContext.Current;
var response = new HttpResponseMessage(HttpStatusCode.OK);
 
var path = context.Server.MapPath("~/App_Data/" + fileName);
if (string.IsNullOrEmpty(fileName) || !File.Exists(path))
{
response = new HttpResponseMessage(HttpStatusCode.NotFound)
{
Content = new StringContent($"<meta charset=\"utf-8\"><h3>【{fileName}】不存在。</h3>", Encoding.UTF8)
};
response.Content.Headers.ContentType = new MediaTypeHeaderValue("text/html");
return response;
}
 
var stream = new FileStream(path, FileMode.Open, FileAccess.Read);
response.Content = new StreamContent(stream);
response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");
response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
{
FileName = HttpUtility.UrlEncode(fileName)
};
response.Headers.Add("Access-Control-Expose-Headers", "FileName");
response.Headers.Add("FileName", HttpUtility.UrlEncode(fileName));
 
return response;
}

 

龙生   17 Aug 2021
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利用404特性同步文件(ASP版)

很久之前写的了，今天分享出来~

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<%
Dim re_url,mainUrl,fso
mainUrl="http://localhost:81"
On Error Resume Next
Set fso=Server.CreateObject("Scripting.FileSystemObject")
Set Retrieval = Server.CreateObject("MSXML2.ServerXMLHTTP")
'获取404地址
If Instr(Request.ServerVariables("HTTP_HOST"),":") > 0 Then
re_url = Replace(Lcase(Request.ServerVariables("QUERY_STRING")),"404;http://"&Request.ServerVariables("HTTP_HOST"),"")
Else
re_url = Replace(Lcase(Request.ServerVariables("QUERY_STRING")),"404;http://"&Request.ServerVariables("HTTP_HOST")&":"&Request.ServerVariables("SERVER_PORT"),"")
End If
 
'只抓取member中的文件
If InStr(re_url,"/member")=0 Then Server.Transfer("/404.html")
If CheckURL(mainUrl&re_url) Then
Call SaveGetFile(re_url,re_url)
Else
'Response.Write(mainUrl&re_url)
Server.Transfer("/404.html")
Response.End
End If
Rem 检测资源是否存在
Function CheckURL(byval A_strUrl)
Retrieval.Open "HEAD", A_strUrl, False
Retrieval.Send()
CheckURL = (Retrieval.Status = 200)
End Function
 
Rem 抓取并保存资源
Function SaveGetFile(RemoteFileUrl,SaveFilePaths)
Dim Ads,GetRemoteData
RemoteFileUrl=ReplaceTest("//+",RemoteFileUrl,"/")
RemoteFileUrlU = Split(RemoteFileUrl, "/")
If InStr(RemoteFileUrlU(UBound(RemoteFileUrlU)),".")=0 Then Server.Transfer("/404.html"):Response.End
' Dim arrFType
' arrFType=Split(RemoteFileUrlU(UBound(RemoteFileUrlU)),".")
' '只抓取静态页面和图片
' Select Case LCase(arrFType(UBound(arrFType)))
' Case "html":
' Case "htm" :
' Case "jpg" :
' Case "jpeg":
' Case "bmp" :
' Case "gif" :
' Case "png":
' Case Else:
' 'Response.Write("2")
' Server.Transfer("/404.html")
' Response.End
' End Select
 
Dim tPath:tPath=""
'文件夹操作
For i=1 To Ubound(RemoteFileUrlU) Step 1
If i<>Ubound(RemoteFileUrlU) Then
If(Not IsFolder(tPath&RemoteFileUrlU(i)))Then
If i=1 Then
Call CreateFolder(RemoteFileUrlU(i))
tPath=tPath&RemoteFileUrlU(i)&"/"
Else
Call CreateFolder(tPath&RemoteFileUrlU(i))
tPath=tPath&RemoteFileUrlU(i)&"/"
End If
Else
tPath=tPath&RemoteFileUrlU(i)&"/"
End If
End If
Next
'Set Retrieval = Server.CreateObject("Microsoft.XMLHTTP")
With Retrieval
.Open "GET", mainUrl&RemoteFileUrl, False, "", ""
.Send
GetRemoteData = .ResponseBody
End With
 
SaveFileName = SaveFilePaths
 
Set Retrieval = Nothing
Set Ads = Server.CreateObject("Adodb.Stream")
 
With Ads
.Type = 1
.Open
.Write GetRemoteData
.SaveToFile Server.MapPath(SaveFileName),2
.Cancel
.Close
End With
Set Ads = Nothing
SaveGetFile = SaveFileName
End Function
Function IsFolder(Folder)
If FSO.FolderExists(Server.MapPath(Folder)) Then  
IsFolder = True
Else
IsFolder = False
End If
End Function
Function CreateFolder(fldr)
Dim f
Set f = FSO.CreateFolder(Server.MapPath(fldr))
CreateFolder = f.Path
Set f=nothing
End Function
Function ts(str)
Response.Write(str)
Response.End
End Function
 
Function ReplaceTest(patrn,str1,replStr)
  Dim regEx
  Set regEx = New RegExp
  regEx.Pattern = patrn
  regEx.IgnoreCase = True
  regEx.Global = True
  ReplaceTest = regEx.Replace(str1,replStr)
End Function
If Err Then
Err.Clear
Server.Transfer("/404.html")
Response.End
End If
'转向抓取过来的资源
'Response.Write("3")
Server.Transfer(re_url)
Response.End
%>

 

龙生   17 Aug 2021
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Your project is not referencing the ".NETFramework,Version=4.5" framework.

我遇到了 Your project is not referencing the “.NETFramework,Version=4.5” framework. Add a reference to “.NETFramework,Version=4.5” in the “frameworks” section of your project.json, and then re-run NuGet restore. 怎么弄都没法解决，我尝试了git撤销更改也无法解决，最后解决方法：删除/obj文件。 来自stackoverflow ———————————————— 版权声明：本文为CSDN博主「迷惘小书童」的原创文章，遵循CC 4.0 BY-SA版权协议，转载请附上原文出处链接及本声明。 原文链接：https://blog.csdn.net/m0_37080285/article/details/90206495

龙生   16 Aug 2021
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Docker镜像大小优化不完全指南(.NET)

以我们家庭好医.netcore项目做个示例，来看看怎么进一步优化Docker镜像的大小。 这里以先编译再做镜像的方法为示例，当然你也可以把编译部分也写进Dockerfile里。   0.先来看看编译后的项目文件大小：39.2MB     1.先看一下VS2019默认Dockerfile生成的镜像 先上Dockerfile

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FROM mcr.microsoft.com/dotnet/aspnet:3.1 AS base
WORKDIR /app
EXPOSE 5000
 
FROM base AS final
WORKDIR /app
COPY . .
ENTRYPOINT ["dotnet", "JTHY.Web.dll"]

  看看生成的镜像大小：265MB   2.用大家常用的slim镜像试试 Dockerfile

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FROM mcr.microsoft.com/dotnet/core/aspnet:3.1-buster-slim AS base
WORKDIR /app
EXPOSE 5000
 
FROM base AS final
WORKDIR /app
COPY /. /app
ENTRYPOINT ["dotnet", "JTHY.Web.dll"]

  镜像大小还是265MB，并没有变小。   3.用大家不常用的alpine镜像来优化 Dockerfile

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ROM mcr.microsoft.com/dotnet/aspnet:3.1-alpine AS base
WORKDIR /app
EXPOSE 5000
 
FROM base AS final
WORKDIR /app
COPY /. /app
ENTRYPOINT ["dotnet", "JTHY.Web.dll"]

  再来看看镜像大小：146MB，是不是很神奇~

龙生   15 Aug 2021
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开发人员正从 Java 8 向 Java 11 转移

此前的 Java 社区报告曾指出，Java 8 仍是开发人员使用的主要版本，新版本并未“得宠”。但 Snyk 近期发布的  JVM Ecosystem Report 2021 则指出，开发人员已经逐渐从 Java 8 迁移到了 Java 11。 JVM Ecosystem Report 2021 展示了关于 JVM 生态系统状态的最大年度调查的结果。该调查在 2021 年 2 月和 3 月的六周时间里进行，收集了来自 2000 多名 Java 开发者的回复。 调查结果显示，有 44.1% 的受访者在生产中使用免费的 AdoptOpenJDK 发行版。但 Oracle 仍然是市场上的重要参与者，其 OpenJDK 构建占 28%，商业 Oracle JDK 占 23%。 40% 的调查参与者在生产中使用了一个以上的 Java 版本。升级到 8 版本以上的人也比预料的要多。目前，有 61.5% 的人在生产中使用 Java 11，近 12% 的人使用最新版本，即调查期间的 Java 15。 Snyk 方面在报告中指出，这表明开发人员确实将他们的 Java 版本升级到了 Java 8 以上的版本，有关大多数 Java 开发人员都乐于使用 Java 8 的现象似乎正在慢慢瓦解。不过值得注意的是，仍有一半的 Java 11 用户（目前使用最多的版本）在他们的生产堆栈中使用 Java 8。 从长远来看，虽然 JVM 语言的种类在过去几年中有所增长，但 Java 仍然是最受欢迎的语言。超过 90% 的开发者使用 Java；Kotlin 次之，为 17.7%。 而 JetBrains IntelliJ IDEA […]

龙生   08 Jul 2021
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在WebApi 中使用AutoFac

参考文档 https://www.cnblogs.com/htsboke/p/10956807.html https://www.cnblogs.com/lenmom/p/8510572.html https://www.cnblogs.com/yaopengfei/p/9479268.html   在WebApi项目中使用AutoFac，结构如下： 首先在Api项目当中引用AutoFac包，如下图所示：   仓储类：

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public interface IUsersRepository
{
int GetUserIsExists(UsersEntity criteria);
 
}
 
 
public class UsersRepository : IUsersRepository
{
Logger log = LogManager.GetLogger("UsersRepository");
 
/// <summary>
/// 获取用户是否存在
/// </summary>
/// <param name="criteria"></param>
/// <returns></returns>
public int GetUserIsExists(UsersEntity criteria)
{
string sql = "。。。。";
try
{
  //查询sql代码，此处省略。。。。            
   }
catch (Exception ex)
{
log.Fatal(ex, "获取用户是否存在异常：{0}，SQL：{1}", ex.Message, sql);
return 0;
}
}
}

服务类：

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//接口  
public interface IUsersService
{
int GetUserIsExists(UsersEntity criteria);
 
}
 
//实现类
public class UsersService : IUsersService
{
private readonly IUsersRepository _usersrepository;    
public UsersService(IUsersRepository usersrepository)    //通过构造函数注入
{
_usersrepository = usersrepository;
}
 
/// <summary>
/// 获取用户是否存在
/// </summary>
/// <param name="criteria"></param>
/// <returns></returns>
public int GetUserIsExists(UsersEntity criteria)
{
return _usersrepository.GetUserIsExists(criteria);
}
}

在Api接口项目中创建一个AutoFac工具类：AutofacUtil.cs

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public class AutofacUtil
{
private static IContainer _container;
 
public static void ConfigureContainer()
{
#region AutoFac IOC容器
 
var builder = new ContainerBuilder();
 
try
{
//builder.RegisterControllers(Assembly.GetCallingAssembly());  //注册mvc控制器  需要引用package Autofac.Mvc
 
//builder.RegisterApiControllers(Assembly.GetExecutingAssembly()).PropertiesAutowired();  //支持Api控制器属性注入
builder.RegisterApiControllers(Assembly.GetCallingAssembly());  //注册所有api控制器  构造函数注入  需要引用package Autofac.WebApi
 
//注册程序集
#region Service
var assemblysServices = Assembly.Load("WebApi.Service");
builder.RegisterAssemblyTypes(assemblysServices)
.AsImplementedInterfaces()
.InstancePerDependency();
#endregion
#region Repository
var assemblysRepository = Assembly.Load("WebApi.Repository");
builder.RegisterAssemblyTypes(assemblysRepository)
.AsImplementedInterfaces()
.InstancePerDependency();
#endregion
 
_container = builder.Build();   //创建依赖注入
 
 
//设置MVC依赖注入
//DependencyResolver.SetResolver(new AutofacDependencyResolver(_container));
 
//设置WebApi依赖注入
GlobalConfiguration.Configuration.DependencyResolver = new AutofacWebApiDependencyResolver(_container);
}
catch (Exception ex)
{
throw new Exception(ex.Message + "\n" + ex.InnerException);
}
#endregion
}
 
/// <summary>
/// 从Autofac容器获取对象
/// </summary>
/// <typeparam name="T"></typeparam>
/// <returns></returns>
public static T GetFromFac<T>()
{
return _container.Resolve<T>();
}
 
}

在 Global.asax.cs 全局中注册一下：

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public class WebApiApplication : System.Web.HttpApplication
{
protected void Application_Start()
{
AreaRegistration.RegisterAllAreas();
GlobalConfiguration.Configure(WebApiConfig.Register);
FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
RouteConfig.RegisterRoutes(RouteTable.Routes);
BundleConfig.RegisterBundles(BundleTable.Bundles);
 
//AutoFac 注册
AutofacUtil.ConfigureContainer();
 
}
}

最后在接口中使用：

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public class UsersController : ApiController
{
private readonly IUsersService _usersService;
public UsersController(IUsersService usersService)    //使用构造函数注入
{
_usersService = usersService;
}
 
 
/// <summary>
/// 获取用户是否存在
/// </summary>
/// <param name="username"></param>
/// <param name="password"></param>
/// <returns></returns>
[HttpPost]
public IHttpActionResult GetUserIsExists(string username, string password)
{
//验证是否存在当前用户
var obModel = new UsersEntity()
{
Username = username,
Password = Encryption.MD5(password)
};
var getresult = _usersService.GetUserIsExists(obModel);
 
return Json(new { isexists = getresult > 0 });
}
}

测试结果：   最后：如果出现 未将对象引用的实例 的错误，检查一下是否引用相应的dll程序集了。   from:https://www.cnblogs.com/peterzhang123/p/12808922.html

龙生   05 Jul 2021
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C# WebRequest请求

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using System;
using System.IO;
using System.Net;
using System.Text;
 
namespace w3cnet.Utils
{
    /// <summary>
    /// Web请求相关
    /// </summary>
    public class WebUtil
    {
        /// <summary>
        /// 获取公网url内容
        /// </summary>
        /// <param name="url"></param>
        /// <returns></returns>
        public static string GetPage(string url)
        {
            return RequestGet(url);
        }
 
        /// <summary>
        /// Post请求
        /// </summary>
        /// <returns></returns>
        public static string RequestGet(string url)
        {
            //请求
            var request = (HttpWebRequest)WebRequest.Create(url);
            request.Timeout = 3600000; //3600秒
 
            //接收
            var response = request.GetResponse();
            var responseStream = response.GetResponseStream();
            if (responseStream != null)
            {
                var reader = new StreamReader(responseStream);
                var result = reader.ReadToEnd();
                reader.Close();
                response.Close();
 
                return result;
            }
 
            return string.Empty;
        }
 
        /// <summary>
        /// Post请求
        /// </summary>
        /// <returns></returns>
        public static string RequestPost(string url, string data = null, Encoding encoding = null)
        {
            if (encoding == null) encoding = Encoding.UTF8;
 
            //请求
            var request = (HttpWebRequest)WebRequest.Create(url);
            request.Method = "POST";
            request.ContentType = "application/x-www-form-urlencoded";
 
            //参数
            if (!string.IsNullOrEmpty(data))
            {
                var byteArray = encoding.GetBytes(data);
 
                request.ContentLength = byteArray.Length;
 
                var requestStream = request.GetRequestStream();
                requestStream.Write(byteArray, 0, byteArray.Length);
                requestStream.Close();
            }
 
            //接收
            var response = request.GetResponse();
            var responseStream = response.GetResponseStream();
            if (responseStream != null)
            {
                var reader = new StreamReader(responseStream, encoding);
                var result = reader.ReadToEnd();
                reader.Close();
                response.Close();
 
                return result;
            }
 
            return string.Empty;
        }
    }
}

 

龙生   04 Jul 2021
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ABP(3.x)切换为MySQL

在EntityFrameworkCore项目下移除包Microsoft.EntityFrameworkCore.SqlServer 在EntityFrameworkCore项目下添加包Pomelo.EntityFrameworkCore.MySql v3.2.4 修改xxxDbContextConfigurer中的 删除EntityFraweorkCore下面的迁移文件夹 EntityFraweorkCore和WebHost的appsettings.json

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"ConnectionStrings": {
    "Default": "server=127.0.0.1;database=abp;uid=root;pwd=123456;charset=utf8mb4;"
},

  添加数据迁移VS菜单：Tools -> NuGet Package Manager -> Package Manager Console运行以下命令：

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Add-Migration DbName

  Update-Database Remove-Migration   from:https://blog.csdn.net/qq_40353040/article/details/108770993

龙生   02 Jul 2021
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java.security.egd

SecureRandom在java各种组件中使用广泛，可以可靠的产生随机数。但在大量产生随机数的场景下，性能会较低。这时可以使用"-Djava.security.egd=file:/dev/./urandom"加快随机数产生过程。 以产生uuid的时候使用nextBytes产生随机数为入口，xSecureRandom的代码逻辑。

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public static UUID randomUUID() {
 
SecureRandom ng =Holder.numberGenerator;
 
 
 
byte[] randomBytes = newbyte[16];
 
ng.nextBytes(randomBytes);
 
randomBytes[6] &= 0x0f; /* clear version */
 
randomBytes[6] |=0x40; /* set to version 4 */
 
randomBytes[8] &= 0x3f; /* clear variant */
 
randomBytes[8] |=0x80; /* set to IETF variant */
 
return newUUID(randomBytes);
 
}
 

使用了SecureRandom.next*的方法。 在使用SecureRandom产生下一个随机数的时候调用nextLong或者nextBytes，最终会调用SecureRandom的nextBytes。

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public long nextLong() {
 
// it's okay that the bottom wordremains signed.
 
return ((long)(next(32)) << 32)+ next(32);
 
}
 
 
 
final protected int next(int numBits) {
 
int numBytes = (numBits+7)/8;
 
byte b[] = new byte[numBytes];
 
int next = 0;
 
 
 
nextBytes(b);
 
for (int i = 0; i < numBytes; i++)
 
next = (next << 8)+ (b[i] & 0xFF);
 
return next >>> (numBytes*8 -numBits);
 
}
 

而nextBytes是一个同步的方法，在多线程使用时，可能会产生性能瓶颈。

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synchronized public void nextBytes(byte[] bytes) {
 
secureRandomSpi.engineNextBytes(bytes);
 
}

  secureRandomSpi被初始化为sun.security.provider.SecureRandom secureRandomSpi是SecureRandom.NativePRNG的一个实例。 使用jvm参数-Djava.security.debug=all ，可以打印securityprovider列表，从中可以看出，SecureRandom.NativePRNG由sun.security.provider.NativePRNG提供服务。 Provider: Set SUN provider property[SecureRandom.NativePRNG/sun.security.provider.NativePRNG]   分析openjdk的源码，NativePRNG.engineNextBytes调用了NativePRNG.RandomIO.ensureBufferValid，而ensureBufferValid直接从urandom读取数据：

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private void ensureBufferValid() throws IOException {
 
...
 
readFully(urandomIn, urandomBuffer);
 
...
 
}

  通过测试可以发现，hotspot需要使用配置项"-Djava.security.egd=file:/dev/./urandom"才能从urandom读取数据，这里openjdk做了优化，直接从urandom读取数据。 /dev/random在产生大量随机数的时候比/dev/urandom慢，所以，建议在大量使用随机数的时候，将随机数发生器指定为/dev/./urandom。   转自：https://blog.51cto.com/leo01/1795447   from:https://blog.csdn.net/wangooo/article/details/109139129

龙生   01 Jul 2021
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