Java和jni(获得指定文件创建时间)

/前言：在我写这篇文章之前，我说说我的碰到这个问题的起因。公司让我写一个jar包，需要获得指定文件的创建日期（日期必须是完整地年月日时分秒）。对于javajdk1.7来说很容易，因为1.7给了我们获得创建日期的接口。但是对于jdk1.6来说，那就是一个老大难，没有提供，只提供了获得最后修改日期的接口。个人收集整理勿做商业用途对于jdk1.6，当然我也查过，请教过好多人，给出了解决办法，那就是使用Java的Runtime去调用当前操作系统的指令获得文件的创建日期：个人收集整理勿做商业用途例如在windows下，publicStringgetFileCreateDate(File_file){Filefile=_file;

try{

Processls_proc=Runtime.getRuntime().exec(

"cmd.exe/cdir"+file.getAbsolutePath()+"/tc");

个人收集整理勿做商业用途BufferedReaderbr=newBufferedReader(newInputStreamReader(ls_proc.getInputStream()));

个人收集整理勿做商业用途for(inti=0;i<5;i++){

br.readLine();

}

Stringstuff=br.readLine();

StringTokenizerst=newStringTokenizer(stuff);

StringdateC=st.nextToken();

Stringtime=st.nextToken();

Stringdatetime=dateC.concat(time);

SimpleDateFormatformatter1=newSimpleDateFormat("yyyy-MM-ddhh:mm:ss");

个人收集整理勿做商业用途SimpleDateFormatformatter2=newSimpleDateFormat(

个人收集整理勿做商业用途"yyyy/MM/ddHH:mm");

datetime=formatter1.format(formatter2.parse(datetime));

个人收集整理勿做商业用途

br.close();

returndatetime;

}catch(Exceptione){

returnnull;

}

}引用：/question/535215288.html但是这个方法只能或得到文件的年月日时分，不能获得到秒。为了获得到秒，最后使用了jni。步骤：1、使用c和C++写一个获得文件创建时间的类#pragmaonce//Modifythefollowingdefinesifyouhavetotargetaplatformpriortotheonesspecifiedbelow.//RefertoMSDNforthelatestinfooncorrespondingvaluesfordifferentplatforms.#ifndefWINVER//AllowuseoffeaturesspecifictoWindowsXPorlater.#defineWINVER0x0501//ChangethistotheappropriatevaluetotargetotherversionsofWindows.#endif#ifndef_WIN32_WINNT//AllowuseoffeaturesspecifictoWindowsXPorlater.#define_WIN32_WINNT0x0501//ChangethistotheappropriatevaluetotargetotherversionsofWindows.#endif#ifndef_WIN32_WINDOWS//AllowuseoffeaturesspecifictoWindows98orlater.#define_WIN32_WINDOWS0x0410//ChangethistotheappropriatevaluetotargetWindowsMeorlater.#endif#ifndef_WIN32_IE//AllowuseoffeaturesspecifictoIE6.0orlater.#define_WIN32_IE0x0600//ChangethistotheappropriatevaluetotargetotherversionsofIE.#endif#defineWIN32_LEAN_AND_MEAN//Excluderarely-usedstufffromWindowsheaders//WindowsHeaderFiles:#include<windows.h>个人收集整理勿做商业用途

//WinFileTime.cpp:DefinestheentrypointfortheDLLapplication.//#include"stdafx.h"#include"FileClass/FileTimeEx.h"#ifdef_MANAGED#pragmamanaged(push,off)#endifBOOLAPIENTRYDllMain(HMODULEhModule,DWORDul_reason_for_call,LPVOIDlpReserved){returnTRUE;}JNIEXPORTjstringJNICALLJava_checkfile_WinFileTime_getFileCreationTime(JNIEnv*env,jobjectcls,jstringFileName){HANDLEhFile;FILETIMEcreationTime;FILETIMElastAccessTime;FILETIMElastWriteTime;FILETIMEcreationLocalTime;SYSTEMTIMEcreationSystemTime;jstringresult;charfileTimeString[30];hFile=CreateFileA((char*)env->GetStringUTFChars(FileName,0),GENERIC_READ,FILE_SHARE_READ|FILE_SHARE_WRITE,NULL,OPEN_EXISTING,0,NULL);if(hFile==INVALID_HANDLE_VALUE)returnenv->NewStringUTF("");if(GetFileTime(hFile,&creationTime,&lastAccessTime,&lastWriteTime)){if(FileTimeToLocalFileTime(&creationTime,&creationLocalTime)){if(FileTimeToSystemTime(&creationLocalTime,&creationSystemTime)){sprintf_s(fileTimeString,"d-d-dd:d:d\0",creationSystemTime.wYear,creationSystemTime.wMonth,creationSystemTime.wDay,creationSystemTime.wHour,creationSystemTime.wMinute,creationSystemTime.wSecond),result=env->NewStringUTF(fileTimeString);}elseresult=env->NewStringUTF("");}elseresult=env->NewStringUTF("");}elseresult=env->NewStringUTF("");CloseHandle(hFile);returnresult;}#ifdef_MANAGED#pragmamanaged(pop)#endif个人收集整理勿做商业用途2、然后生成动态链接文件（*.dll），将这个文件放到C:\Windows\System32和你的javajdk目录下D:\ProgramFiles\Java\jdk1.6.0_18\jre\bin。个人收集整理勿做商业用途3、java文件中写法publicfinalclassWinFileTime{static{System.loadLibrary("WinFileTime");}privatestaticnativeStringgetFileCreationTime(StringfileName);publicstaticStringgetCreationTime(StringfileName){returngetFileCreationTime(fileName);}}}个人收集整理勿做商业用途注意：头文件与类文件的方法名必须与java中的类名一直，如：c中是Java_checkfile_WinFileTime_getFileCreationTime,那么java中就是checkfile.WinFileTime.getFileCreationTime(checkfile是包名，WinFileTime是类名，getFileCreationTime是方法名).个人收集整理勿做商业用途jdk1.7方法：下载一个jdk1.7帮助文档，看看这个类BasicFileAttributeView。Pathpath=Paths.get(filePath);

BasicFileAttributeViewbasicview=Files.getFi