用java建立檔案夾
package test;
public class mulutest
{
public static void main(string[] args)
mulutest mulutest = new mulutest();
mulutest.newfolder("d:\\abcds");
}
public void newfolder(string folderpath)
string filepath = folderpath;
filepath = filepath.tostring();
java.io.file myfilepath = new java.io.file(filepath);
try
{
if(myfilepath.isdirectory())
{
system.out.println("the directory isexists!");
}
else
myfilepath.mkdir();
system.out.println("建立目錄成功");
}
catch (exception e)
system.out.println("建立目錄操作出錯");
e.printstacktrace();
package ifpre.web;
import gxdmif.gxstringutil;
import java.io.dataoutputstream;
import java.io.file;
import java.io.fileoutputstream;
import java.io.inputstream;
import org.springframework.web.multipart.multipartfile;
public class savefile {
public boolean save(string path, multipartfile file) throws exception {
gxstringutil gx = new gxstringutil();
boolean result = false ;
file dirfile = null ;
try {
dirfile = new file(path);
if ( ! (dirfile.exists()) && !(dirfile.isdirectory())) {
boolean creadok = dirfile.mkdirs();
if (creadok) {
system.out.println( "ok:建立檔案夾成功!" );
} else {
system.out.println( "err:建立檔案夾失敗!" );
}
}
} catch (exception e) {
e.printstacktrace();
system.out.println(e);
return false ;
}
if (file != null && ! file.isempty()) {
string fullpath = path + system.getproperty( "file.separator " )
+ gx.netstringtogbk(file.getoriginalfilename());
dataoutputstream out = null ;
inputstream is = null ;
try {
out = new dataoutputstream( new fileoutputstream(fullpath));
is = file.getinputstream();
byte [] buffer = new byte [ 1024 ];
while (is.read(buffer) > 0 ) {
out.write(buffer);
} finally {
if (is != null ) {
is.close();
if (out != null ) {
out.close();
result = true ;
return result;
}
public boolean delete(string path, multipartfile file) throws exception {
if (file != null && ! file.isempty()) {
+ gx.netstringtogbk(file.getoriginalfilename());
file file2 = new file(fullpath);
file2.delete();
result = true ;
} catch (exception e) {
e.printstacktrace();
result = false;
public boolean deletefolder(file folder) {
string childs[] = folder.list();
if (childs == null || childs.length <= 0 ) {
if(folder.delete()) {
result = true ;
}
} else {
for ( int i = 0 ; i < childs.length; i ++ ) {
string childname = childs[i];
string childpath =
folder.getpath() + file.separator + childname;
file filepath = new file(childpath);
if (filepath.exists() && filepath.isfile()) {
if(filepath.delete()) {
result = true ;
} else {
result = false ;
break ;
}
}
else if (filepath.exists() && filepath.isdirectory()) {
if(deletefolder(filepath)) {
} else {
}
folder.delete();
} catch (exception e) {
e.printstacktrace();
result = false ;
}
150%;�yac���8~�amily:simsun;mso-hansi-font-family:simsun;color:#323e32'>十進制整數轉換成二進制整數,傳回結果是一個字元串:
integer.tobinarystring(int i);
integer和long提供了tobinarystring,tohexstring和tooctalstring方法,可以友善的将資料轉換成二進制、十六進制和八進制字元串。功能更加強大的是其tostring(int/long i, int radix)方法,可以将一個十進制數轉換成任意進制的字元串形式。
byte, short, float和double等資料類型,可以利用integer或者是long的tobinarystring, tohexstring, to octalstring和tostring方法轉換成其他進制的字元串形式。
4 其它進制到十進制的轉換
五進制字元串14414轉換成十進制整數,結果是1234:
system.out.println(integer.valueof("14414", 5);
integer和long提供的valueof(stringsource, int radix)方法,可以将任意進制的字元串轉換成十進制資料。
5 整數到位元組數組的轉換
public static byte[] tobytearray(int number)
int temp = number;
byte[] b=new byte[4];
for (int i = b.length - 1; i > -1; i--)
b[i] = new integer(temp & 0xff).bytevalue();
temp = temp >> 8;
return b;
6 位元組數組到整數的轉換
public static int tointeger(byte[] b)
int s = 0;
for (int i = 0; i < 3; i++)
if (b[i] > 0)
s = s + b[i];
else
s = s + 256 + b[i];
s = s * 256;
if (b[3] > 0)
s = s + b[3];
s = s + 256 + b[3];
return s;
7 短整數與位元組數組之間的互相轉換
short與int之間的差別在于short是兩個位元組的,而int是四個位元組的。是以,隻需要将5 與6 中的範例程式小做改動,即可實作短整數與位元組數組之間的互相轉換。
8 位元組數組轉換成雙精度浮點數
public double todouble(byte[] b)
long l = 0;
double d = new double(0.0);
l = b[0];
l |= ((long)b[1]<<8);
l |= ((long)b[2]<<16);
l |= ((long)b[3]<<24);
l |= ((long)b[4]<<32);
l |= ((long)b[5]<<40);
l |= ((long)b[6]<<48);
l |= ((long)b[7]<<56);
return d.longbitstodouble(l);
9 布爾類型轉換成字元串
第一種方法是:
boolean bool = true;
string s = new boolean(bool).tostring();//将bool利用對象封裝器轉化為對象
s.equals("true");
第二種方法是:
string s = string.valueof( bool );
首先,從代碼長度上講第二種方法明顯要比第一種方法簡潔;其次,第一種方法在轉化過程中多引入了一個完全沒有必要的對象,是以,相對第二種方法來說這就造成了記憶體空間的浪費,大大減慢了運作速度。是以,推薦使用第二種方法。
10 數字類型與數字類對象之間的轉換
byte b = 169;
byte bo = new byte( b );
b = bo.bytevalue();
short t = 169;
short to = new short( t );
t = to.shortvalue();
int i = 169;
integer io = new integer( i );
i = io.intvalue();
long l = 169;
long lo = new long( l );
l = lo.longvalue();
float f = 169f;
float fo = new float( f );
f = fo.floatvalue();
double d = 169f;
double dobj = new double( d );
d = dobj.doublevalue();
5.0 string 轉integer
integer in=new integer(string s);
integer in=new integer(integer.parseint(string s));
5.1 string 轉 int
1). int i = integer.parseint([string]); 或
i = integer.parseint([string],[int radix]);
2). int i = integer.valueof(my_str).intvalue();
5.2 如何将整數 int 轉換成字串 string ?
a. 有叁種方法:
1.) string s = string.valueof(i);
2.) string s = integer.tostring(i);
3.) string s = "" + i;
注:double, float, long 轉成字串的方法大同小異.
5.3 string 轉date
導入 java.util.date date=null;
date=java.sql.date.valueof(string s);