求MD4 java实现的代码

作者&投稿:辕裴 (若有异议请与网页底部的电邮联系)
用JAVA程序实现消息摘要算法,并生成一个数的消息摘要~

import java.security.MessageDigest;

String myinfo="我的测试信息";

MessageDigest alg = MessageDigest.getInstance("MD5");
alga.update(myinfo.getBytes());
byte[] bytes = alga.digest();

这里有各种加密算法的demo,MD5、MD2、MD4、SHA1、SHA512、Base64、AES、DES、DH、DSA、HMAC、PBE、RSA,应有尽有
https://github.com/beat-the-buzzer/CryptTest.git

//以下为直接复制粘帖过来的

import java.lang.reflect.*;

/************************************************
MD5 算法的Java Bean
@author:Topcat Tuppin
Last Modified:10,Mar,2001
*************************************************/

/*******************************************************************************
* md5 类实现了RSA Data Security, Inc.在提交给IETF 的RFC1321中的MD5 message-digest 算法。
******************************************************************************/

public class MD5 {
/*
* 下面这些S11-S44实际上是一个4*4的矩阵,在原始的C实现中是用#define 实现的, 这里把它们实现成为static
* final是表示了只读,切能在同一个进程空间内的多个 Instance间共享
*/
static final int S11 = 7;

static final int S12 = 12;

static final int S13 = 17;

static final int S14 = 22;

static final int S21 = 5;

static final int S22 = 9;

static final int S23 = 14;

static final int S24 = 20;

static final int S31 = 4;

static final int S32 = 11;

static final int S33 = 16;

static final int S34 = 23;

static final int S41 = 6;

static final int S42 = 10;

static final int S43 = 15;

static final int S44 = 21;

static final byte[] PADDING = { -128, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0 };

/*
* 下面的三个成员是MD5计算过程中用到的3个核心数据,在原始的C实现中 被定义到MD5_CTX结构中
*/
private long[] state = new long[4]; // state (ABCD)

private long[] count = new long[2]; // number of bits, modulo 2^64 (lsb
// first)

private byte[] buffer = new byte[64]; // input buffer

/*
* digestHexStr是MD5的唯一一个公共成员,是最新一次计算结果的 16进制ASCII表示.
*/
public String digestHexStr;

/*
* digest,是最新一次计算结果的2进制内部表示,表示128bit的MD5值.
*/
private byte[] digest = new byte[16];

/*
* getMD5ofStr是类MD5最主要的公共方法,入口参数是你想要进行MD5变换的字符串
* 返回的是变换完的结果,这个结果是从公共成员digestHexStr取得的.
*/
public String getMD5ofStr(String inbuf) {
md5Init();
md5Update(inbuf.getBytes(), inbuf.length());
md5Final();
digestHexStr = "";
for (int i = 0; i < 16; i++) {
digestHexStr += byteHEX(digest[i]);
}
return digestHexStr;

}

// 这是MD5这个类的标准构造函数,JavaBean要求有一个public的并且没有参数的构造函数
public MD5() {
md5Init();

return;
}

/* md5Init是一个初始化函数,初始化核心变量,装入标准的幻数 */
private void md5Init() {
count[0] = 0L;
count[1] = 0L;
///* Load magic initialization constants.

state[0] = 0x67452301L;
state[1] = 0xefcdab89L;
state[2] = 0x98badcfeL;
state[3] = 0x10325476L;

return;
}

/*
* F, G, H ,I 是4个基本的MD5函数,在原始的MD5的C实现中,由于它们是
* 简单的位运算,可能出于效率的考虑把它们实现成了宏,在java中,我们把它们 实现成了private方法,名字保持了原来C中的。
*/

private long F(long x, long y, long z) {
return (x & y) | ((~x) & z);

}

private long G(long x, long y, long z) {
return (x & z) | (y & (~z));

}

private long H(long x, long y, long z) {
return x ^ y ^ z;
}

private long I(long x, long y, long z) {
return y ^ (x | (~z));
}

/*
* FF,GG,HH和II将调用F,G,H,I进行近一步变换 FF, GG, HH, and II transformations for
* rounds 1, 2, 3, and 4. Rotation is separate from addition to prevent
* recomputation.
*/

private long FF(long a, long b, long c, long d, long x, long s, long ac) {
a += F(b, c, d) + x + ac;
a = ((int) a << s) | ((int) a >>> (32 - s));
a += b;
return a;
}

private long GG(long a, long b, long c, long d, long x, long s, long ac) {
a += G(b, c, d) + x + ac;
a = ((int) a << s) | ((int) a >>> (32 - s));
a += b;
return a;
}

private long HH(long a, long b, long c, long d, long x, long s, long ac) {
a += H(b, c, d) + x + ac;
a = ((int) a << s) | ((int) a >>> (32 - s));
a += b;
return a;
}

private long II(long a, long b, long c, long d, long x, long s, long ac) {
a += I(b, c, d) + x + ac;
a = ((int) a << s) | ((int) a >>> (32 - s));
a += b;
return a;
}

/*
* md5Update是MD5的主计算过程,inbuf是要变换的字节串,inputlen是长度,这个
* 函数由getMD5ofStr调用,调用之前需要调用md5init,因此把它设计成private的
*/
private void md5Update(byte[] inbuf, int inputLen) {

int i, index, partLen;
byte[] block = new byte[64];
index = (int) (count[0] >>> 3) & 0x3F;
// /* Update number of bits */
if ((count[0] += (inputLen << 3)) < (inputLen << 3))
count[1]++;
count[1] += (inputLen >>> 29);

partLen = 64 - index;

// Transform as many times as possible.
if (inputLen >= partLen) {
md5Memcpy(buffer, inbuf, index, 0, partLen);
md5Transform(buffer);

for (i = partLen; i + 63 < inputLen; i += 64) {

md5Memcpy(block, inbuf, 0, i, 64);
md5Transform(block);
}
index = 0;

} else

i = 0;

///* Buffer remaining input */
md5Memcpy(buffer, inbuf, index, i, inputLen - i);

}

/*
* md5Final整理和填写输出结果
*/
private void md5Final() {
byte[] bits = new byte[8];
int index, padLen;

///* Save number of bits */
Encode(bits, count, 8);

///* Pad out to 56 mod 64.
index = (int) (count[0] >>> 3) & 0x3f;
padLen = (index < 56) ? (56 - index) : (120 - index);
md5Update(PADDING, padLen);

///* Append length (before padding) */
md5Update(bits, 8);

///* Store state in digest */
Encode(digest, state, 16);

}

/*
* md5Memcpy是一个内部使用的byte数组的块拷贝函数,从input的inpos开始把len长度的
* 字节拷贝到output的outpos位置开始
*/

private void md5Memcpy(byte[] output, byte[] input, int outpos, int inpos,
int len) {
int i;

for (i = 0; i < len; i++)
output[outpos + i] = input[inpos + i];
}

/*
* md5Transform是MD5核心变换程序,有md5Update调用,block是分块的原始字节
*/
private void md5Transform(byte block[]) {
long a = state[0], b = state[1], c = state[2], d = state[3];
long[] x = new long[16];

Decode(x, block, 64);

/* Round 1 */
a = FF(a, b, c, d, x[0], S11, 0xd76aa478L); /* 1 */
d = FF(d, a, b, c, x[1], S12, 0xe8c7b756L); /* 2 */
c = FF(c, d, a, b, x[2], S13, 0x242070dbL); /* 3 */
b = FF(b, c, d, a, x[3], S14, 0xc1bdceeeL); /* 4 */
a = FF(a, b, c, d, x[4], S11, 0xf57c0fafL); /* 5 */
d = FF(d, a, b, c, x[5], S12, 0x4787c62aL); /* 6 */
c = FF(c, d, a, b, x[6], S13, 0xa8304613L); /* 7 */
b = FF(b, c, d, a, x[7], S14, 0xfd469501L); /* 8 */
a = FF(a, b, c, d, x[8], S11, 0x698098d8L); /* 9 */
d = FF(d, a, b, c, x[9], S12, 0x8b44f7afL); /* 10 */
c = FF(c, d, a, b, x[10], S13, 0xffff5bb1L); /* 11 */
b = FF(b, c, d, a, x[11], S14, 0x895cd7beL); /* 12 */
a = FF(a, b, c, d, x[12], S11, 0x6b901122L); /* 13 */
d = FF(d, a, b, c, x[13], S12, 0xfd987193L); /* 14 */
c = FF(c, d, a, b, x[14], S13, 0xa679438eL); /* 15 */
b = FF(b, c, d, a, x[15], S14, 0x49b40821L); /* 16 */

/* Round 2 */
a = GG(a, b, c, d, x[1], S21, 0xf61e2562L); /* 17 */
d = GG(d, a, b, c, x[6], S22, 0xc040b340L); /* 18 */
c = GG(c, d, a, b, x[11], S23, 0x265e5a51L); /* 19 */
b = GG(b, c, d, a, x[0], S24, 0xe9b6c7aaL); /* 20 */
a = GG(a, b, c, d, x[5], S21, 0xd62f105dL); /* 21 */
d = GG(d, a, b, c, x[10], S22, 0x2441453L); /* 22 */
c = GG(c, d, a, b, x[15], S23, 0xd8a1e681L); /* 23 */
b = GG(b, c, d, a, x[4], S24, 0xe7d3fbc8L); /* 24 */
a = GG(a, b, c, d, x[9], S21, 0x21e1cde6L); /* 25 */
d = GG(d, a, b, c, x[14], S22, 0xc33707d6L); /* 26 */
c = GG(c, d, a, b, x[3], S23, 0xf4d50d87L); /* 27 */
b = GG(b, c, d, a, x[8], S24, 0x455a14edL); /* 28 */
a = GG(a, b, c, d, x[13], S21, 0xa9e3e905L); /* 29 */
d = GG(d, a, b, c, x[2], S22, 0xfcefa3f8L); /* 30 */
c = GG(c, d, a, b, x[7], S23, 0x676f02d9L); /* 31 */
b = GG(b, c, d, a, x[12], S24, 0x8d2a4c8aL); /* 32 */

/* Round 3 */
a = HH(a, b, c, d, x[5], S31, 0xfffa3942L); /* 33 */
d = HH(d, a, b, c, x[8], S32, 0x8771f681L); /* 34 */
c = HH(c, d, a, b, x[11], S33, 0x6d9d6122L); /* 35 */
b = HH(b, c, d, a, x[14], S34, 0xfde5380cL); /* 36 */
a = HH(a, b, c, d, x[1], S31, 0xa4beea44L); /* 37 */
d = HH(d, a, b, c, x[4], S32, 0x4bdecfa9L); /* 38 */
c = HH(c, d, a, b, x[7], S33, 0xf6bb4b60L); /* 39 */
b = HH(b, c, d, a, x[10], S34, 0xbebfbc70L); /* 40 */
a = HH(a, b, c, d, x[13], S31, 0x289b7ec6L); /* 41 */
d = HH(d, a, b, c, x[0], S32, 0xeaa127faL); /* 42 */
c = HH(c, d, a, b, x[3], S33, 0xd4ef3085L); /* 43 */
b = HH(b, c, d, a, x[6], S34, 0x4881d05L); /* 44 */
a = HH(a, b, c, d, x[9], S31, 0xd9d4d039L); /* 45 */
d = HH(d, a, b, c, x[12], S32, 0xe6db99e5L); /* 46 */
c = HH(c, d, a, b, x[15], S33, 0x1fa27cf8L); /* 47 */
b = HH(b, c, d, a, x[2], S34, 0xc4ac5665L); /* 48 */

/* Round 4 */
a = II(a, b, c, d, x[0], S41, 0xf4292244L); /* 49 */
d = II(d, a, b, c, x[7], S42, 0x432aff97L); /* 50 */
c = II(c, d, a, b, x[14], S43, 0xab9423a7L); /* 51 */
b = II(b, c, d, a, x[5], S44, 0xfc93a039L); /* 52 */
a = II(a, b, c, d, x[12], S41, 0x655b59c3L); /* 53 */
d = II(d, a, b, c, x[3], S42, 0x8f0ccc92L); /* 54 */
c = II(c, d, a, b, x[10], S43, 0xffeff47dL); /* 55 */
b = II(b, c, d, a, x[1], S44, 0x85845dd1L); /* 56 */
a = II(a, b, c, d, x[8], S41, 0x6fa87e4fL); /* 57 */
d = II(d, a, b, c, x[15], S42, 0xfe2ce6e0L); /* 58 */
c = II(c, d, a, b, x[6], S43, 0xa3014314L); /* 59 */
b = II(b, c, d, a, x[13], S44, 0x4e0811a1L); /* 60 */
a = II(a, b, c, d, x[4], S41, 0xf7537e82L); /* 61 */
d = II(d, a, b, c, x[11], S42, 0xbd3af235L); /* 62 */
c = II(c, d, a, b, x[2], S43, 0x2ad7d2bbL); /* 63 */
b = II(b, c, d, a, x[9], S44, 0xeb86d391L); /* 64 */

state[0] += a;
state[1] += b;
state[2] += c;
state[3] += d;

}

/*
* Encode把long数组按顺序拆成byte数组,因为java的long类型是64bit的, 只拆低32bit,以适应原始C实现的用途
*/
private void Encode(byte[] output, long[] input, int len) {
int i, j;

for (i = 0, j = 0; j < len; i++, j += 4) {
output[j] = (byte) (input[i] & 0xffL);
output[j + 1] = (byte) ((input[i] >>> 8) & 0xffL);
output[j + 2] = (byte) ((input[i] >>> 16) & 0xffL);
output[j + 3] = (byte) ((input[i] >>> 24) & 0xffL);
}
}

/*
* Decode把byte数组按顺序合成成long数组,因为java的long类型是64bit的,
* 只合成低32bit,高32bit清零,以适应原始C实现的用途
*/
private void Decode(long[] output, byte[] input, int len) {
int i, j;

for (i = 0, j = 0; j < len; i++, j += 4)
output[i] = b2iu(input[j]) | (b2iu(input[j + 1]) << 8)
| (b2iu(input[j + 2]) << 16) | (b2iu(input[j + 3]) << 24);

return;
}

/*
* b2iu是我写的一个把byte按照不考虑正负号的原则的”升位”程序,因为java没有unsigned运算
*/
public static long b2iu(byte b) {
return b < 0 ? b & 0x7F + 128 : b;
}

/*
* byteHEX(),用来把一个byte类型的数转换成十六进制的ASCII表示,
* 因为java中的byte的toString无法实现这一点,我们又没有C语言中的 sprintf(outbuf,"%02X",ib)
*/
public static String byteHEX(byte ib) {
char[] Digit = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A',
'B', 'C', 'D', 'E', 'F' };
char[] ob = new char[2];
ob[0] = Digit[(ib >>> 4) & 0X0F];
ob[1] = Digit[ib & 0X0F];
String s = new String(ob);
return s;
}

public static void main(String args[]) {

MD5 m = new MD5();
if (Array.getLength(args) == 0) { //如果没有参数,执行标准的Test Suite

System.out.println("MD5 Test suite:");
System.out.println("MD5(\"Admin\"):" + m.getMD5ofStr("Admin"));
System.out.println("MD5(\"a\"):" + m.getMD5ofStr("a"));
System.out.println("MD5(\"abc\"):" + m.getMD5ofStr("abc"));
System.out.println("MD5(\"message digest\"):"
+ m.getMD5ofStr("message digest"));
System.out.println("MD5(\"abcdefghijklmnopqrstuvwxyz\"):"
+ m.getMD5ofStr("abcdefghijklmnopqrstuvwxyz"));
System.out
.println("MD5(\"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789\"):"
+ m
.getMD5ofStr("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"));
} else
System.out
.println("MD5(" + args[0] + ")=" + m.getMD5ofStr(args[0]));

}

}

public class MD4 {

private static int A, B, C, D;

private static int X[] = new int[16];

private static int F(int X, int Y, int Z) {
return (X & Y) | ((~X) & Z);
}

private static int G(int X, int Y, int Z) {
return (X & Y) | (X & Z) | (Y & Z);
}

private static int H(int X, int Y, int Z) {
return X ^ Y ^ Z;
}

private static int lshift(int x, int s) {
if (s == 0) {
return x;
}
return (((x << s) & 0xFFFFFFFF) | ((x >> (32 - s)) & (0x7FFFFFFF >> (31 - s))));
}

private static int ROUND1(int a, int b, int c, int d, int k, int s) {
return (lshift(a + F(b, c, d) + X[k], s));
}

private static int ROUND2(int a, int b, int c, int d, int k, int s) {
return (lshift(a + G(b, c, d) + X[k] + (int) 0x5A827999, s));
}

private static int ROUND3(int a, int b, int c, int d, int k, int s) {
return (lshift(a + H(b, c, d) + X[k] + (int) 0x6ED9EBA1, s));
}

public static void mdfour64(int M[]) {
int j;
int AA, BB, CC, DD;

for (j = 0; j < 16; j++) {
X[j] = M[j];
}

AA = A;
BB = B;
CC = C;
DD = D;

A = ROUND1(A, B, C, D, 0, 3);
D = ROUND1(D, A, B, C, 1, 7);
C = ROUND1(C, D, A, B, 2, 11);
B = ROUND1(B, C, D, A, 3, 19);
A = ROUND1(A, B, C, D, 4, 3);
D = ROUND1(D, A, B, C, 5, 7);
C = ROUND1(C, D, A, B, 6, 11);
B = ROUND1(B, C, D, A, 7, 19);
A = ROUND1(A, B, C, D, 8, 3);
D = ROUND1(D, A, B, C, 9, 7);
C = ROUND1(C, D, A, B, 10, 11);
B = ROUND1(B, C, D, A, 11, 19);
A = ROUND1(A, B, C, D, 12, 3);
D = ROUND1(D, A, B, C, 13, 7);
C = ROUND1(C, D, A, B, 14, 11);
B = ROUND1(B, C, D, A, 15, 19);

A = ROUND2(A, B, C, D, 0, 3);
D = ROUND2(D, A, B, C, 4, 5);
C = ROUND2(C, D, A, B, 8, 9);
B = ROUND2(B, C, D, A, 12, 13);
A = ROUND2(A, B, C, D, 1, 3);
D = ROUND2(D, A, B, C, 5, 5);
C = ROUND2(C, D, A, B, 9, 9);
B = ROUND2(B, C, D, A, 13, 13);
A = ROUND2(A, B, C, D, 2, 3);
D = ROUND2(D, A, B, C, 6, 5);
C = ROUND2(C, D, A, B, 10, 9);
B = ROUND2(B, C, D, A, 14, 13);
A = ROUND2(A, B, C, D, 3, 3);
D = ROUND2(D, A, B, C, 7, 5);
C = ROUND2(C, D, A, B, 11, 9);
B = ROUND2(B, C, D, A, 15, 13);

A = ROUND3(A, B, C, D, 0, 3);
D = ROUND3(D, A, B, C, 8, 9);
C = ROUND3(C, D, A, B, 4, 11);
B = ROUND3(B, C, D, A, 12, 15);
A = ROUND3(A, B, C, D, 2, 3);
D = ROUND3(D, A, B, C, 10, 9);
C = ROUND3(C, D, A, B, 6, 11);
B = ROUND3(B, C, D, A, 14, 15);
A = ROUND3(A, B, C, D, 1, 3);
D = ROUND3(D, A, B, C, 9, 9);
C = ROUND3(C, D, A, B, 5, 11);
B = ROUND3(B, C, D, A, 13, 15);
A = ROUND3(A, B, C, D, 3, 3);
D = ROUND3(D, A, B, C, 11, 9);
C = ROUND3(C, D, A, B, 7, 11);
B = ROUND3(B, C, D, A, 15, 15);

A += AA;
B += BB;
C += CC;
D += DD;

A &= 0xFFFFFFFF;
B &= 0xFFFFFFFF;
C &= 0xFFFFFFFF;
D &= 0xFFFFFFFF;
}

public static void copy64(int M[], byte in[], int offset) {
int i;
for (i = 0; i < 16; i++) {
M[i] = ((in[offset + i * 4 + 3] << 24) & 0xFF000000)
| ((in[offset + i * 4 + 2] << 16) & 0xFF0000)
| ((in[offset + i * 4 + 1] << 8) & 0xFF00)
| (((int) in[offset + i * 4 + 0]) & 0xFF);
}
}

public static void copy64(int M[], byte in[]) {
copy64(M, in, 0);
}

public static void copy4(byte out[], int offset, int x) {
out[offset] = (byte) (x & 0xFF);
out[1 + offset] = (byte) ((x >> 8) & 0xFF);
out[2 + offset] = (byte) ((x >> 16) & 0xFF);
out[3 + offset] = (byte) ((x >> 24) & 0xFF);
}

public static byte[] mdfour(byte in[]) {
byte out[] = new byte[16];
byte buf[] = new byte[128];
int n = in.length;
int M[] = new int[16];
int b = n * 8;
int i;
int offset;

A = 0x67452301;
B = 0xefcdab89;
C = 0x98badcfe;
D = 0x10325476;

offset = 0;
while (n > 64) {
copy64(M, in, offset);
mdfour64(M);
offset += 64;
n -= 64;
}

for (i = 0; i < 128; i++) {
buf[i] = (i + offset < in.length) ? in[offset + i] : 0;
}
buf[n] = (byte) 0x80;

if (n <= 55) {
copy4(buf, 56, b);
copy64(M, buf);
mdfour64(M);
} else {
copy4(buf, 120, b);
copy64(M, buf);
mdfour64(M);
copy64(M, buf, 64);
mdfour64(M);
}

for (i = 0; i < 128; i++) {
buf[i] = 0;
}
copy64(M, buf);

copy4(out, 0, A);
copy4(out, 4, B);
copy4(out, 8, C);
copy4(out, 12, D);

A = B = C = D = 0;
return out;
}

private static final char[] HEX_DIGITS = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };

public static String toHexString(byte[] b) {
return toHexString(b, 0, b.length);
}

public static String toHexString(byte[] b, int off, int len) {
char[] buf = new char[len * 2];
for (int i = 0, j = 0, k; i < len;) {
k = b[off + i++];
buf[j++] = HEX_DIGITS[(k >>> 4) & 0x0F];
buf[j++] = HEX_DIGITS[k & 0x0F];
}
return new String(buf);
}

private static String getTestResult(String s) {
return toHexString(mdfour(s.getBytes()));
}

public static void main(String[] args) {
System.out.println(getTestResult(""));
System.out.println(getTestResult("a"));
System.out.println(getTestResult("abc"));
System.out.println(getTestResult("message digest"));
System.out.println(getTestResult("abcdefghijklmnopqrstuvwxyz"));
System.out.println(getTestResult("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"));
System.out.println(getTestResult("12345678901234567890123456789012345678901234567890123456789012345678901234567890"));
}

}


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须晶康复: //以下为直接复制粘帖过来的import java.lang.reflect.*;/************************************************ MD5 算法的Java Bean @author:Topcat Tuppin Last Modified:10,Mar,2001 *************************************************//************************************...

伊通满族自治县18471916788: 求质数1 - 1000java的源代码 -
须晶康复: public static void main(String[] args){ boolean flag = true; int [] sum = new int[1000]; int num = 0; for(int i=1;i

伊通满族自治县18471916788: md5生成64个字符串的java代码 -
须晶康复: 可以参考Apache commons digest 的md5实现

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须晶康复: import java.awt.event.*; import javax.swing.*; public class FrameTest { public static void main(String[] args) { new F().setVisible(true); } } class F extends JFrame implements ActionListener{ JCheckBox a,b,c; JRadioButton d,e,f; ButtonGroup g; F(){ ...

伊通满族自治县18471916788: 求Java的程序代码
须晶康复: public class Test { public static void main(String[] args) { System.out.println("Hello word!!!"); } }

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须晶康复: package com.javase.test.demo; import java.util.Random; public class XXX { public static void main(String args[]) { int array[][] = new int[3][4]; for (int i = 0; i < 3; i++) { for (int j = 0; j < 4; j++) { array[i][j] = new Random().nextInt(100); } } showArray(array); ...

伊通满族自治县18471916788: 求大量JAVA实现dos命令的代码
须晶康复: Process process = Runtime.getRuntime().exec("cmd /c del f:\\aaa.doc");

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须晶康复: 你百度找一下“quartz定时器”或“Spring quartz定时器”.它可以配置订好几时去执行一下程序,也可以定好每间隔一段时间去执行一个程序,我相信你按照上面的肯定可以找到你需要的,网上写的都特别详细了.如果找不到或不明白,再做留言

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须晶康复: class A { public static void main(String arg[]) { int k=1000; while (k 0) { 畅定扳剐殖溉帮税爆粳 a=temp%10; sum+=a*a*a*a; temp/=10; } if(sum==k) return true; else return false; } public static boolean IsPrime(int k) { if (k == 2) return true; else if (k % 2 == 0) return false; else { for (int i = 2; i

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须晶康复: } } //3;,语数外平均分;/数组存放从控制台输入的学生信息进行封装 Student[] stu = new Student[5]; //.school = school; System.out.println("请输入学生信息:"); for(int i = 0;i&lt,语数外总分; stu.length:" j++){ Student temp; if(stu[i].sum()

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