java.math.BigInteger.toString java code examples

Refine search

Common ways to obtain BigInteger

private void myMethod () {
 BigInteger b =String value;new BigInteger(value)
new BigInteger(1, magnitude)
new BigInteger(value)
Smart code suggestions by Codota
}

 import java.security.SecureRandom;
import java.math.BigInteger;

public final class SessionIdentifierGenerator {
 private SecureRandom random = new SecureRandom();

 public String nextSessionId() {
  return new BigInteger(130, random).toString(32);
 }
}

 String plaintext = "your text here";
MessageDigest m = MessageDigest.getInstance("MD5");
m.reset();
m.update(plaintext.getBytes());
byte[] digest = m.digest();
BigInteger bigInt = new BigInteger(1,digest);
String hashtext = bigInt.toString(16);
// Now we need to zero pad it if you actually want the full 32 chars.
while(hashtext.length() < 32 ){
 hashtext = "0"+hashtext;
}

private String checksum(String gherkin) {
  return new BigInteger(1, md5.digest(gherkin.getBytes(UTF8))).toString(16);
}

 BigInteger bi = new BigInteger("76292708057987193002565060032465481997");
System.out.println(bi.toString(16));

private static void testBigInteger() {
  System.out.println("Running BigInteger benchmark");
  BigInteger result = BigInteger.ONE;
  for (int j = 0; j < 100; ++j) {
    long start = System.currentTimeMillis();
    for (int k = 0; k < 5000; ++k) {
      BigInteger a = BigInteger.ZERO;
      BigInteger b = BigInteger.ONE;
      for (int i = 0; i < 1000; ++i) {
        BigInteger c = a.add(b);
        a = b;
        b = c;
      }
      result = a;
    }
    long end = System.currentTimeMillis();
    System.out.println("Operation took " + (end - start) + " milliseconds");
  }
  System.out.println(result.toString());
}

 @Override
 public String rename(String filePath) {
  try {
   MessageDigest md = MessageDigest.getInstance("MD5");
   md.update(filePath.getBytes());
   return new BigInteger(1, md.digest()).toString(32);
  } catch (NoSuchAlgorithmException e) {
   e.printStackTrace();
  }
  return "";
 }
})

public static void main3(String[] args) {
  String key = "7b104953fb112826";
  String pubKey = "010001";
  String m = "157794750267131502212476817800345498121872783333389747424011531025366277535262539913701806290766479189477533597854989606803194253978660329941980786072432806427833685472618792592200595694346872951301770580765135349259590167490536138082469680638514416594216629258349130257685001248172188325316586707301643237607";
  try {
    String k = reverse(key);
    String keyTo16 = toHex(k, "GBK");
    // System.out.println(new BigInteger(keyTo16, 16));
    // new BigInteger(keyTo16, 16) 字符串转为16进制数字，
    // pow(Integer.valueOf(pubKey, 16)) 得到次方的值
    //remainder 取余数
    String c = (new BigInteger(keyTo16, 16).pow(Integer.valueOf(pubKey, 16))).remainder(new BigInteger(m)) + "";
    //转为16进制表示
    System.out.println(new BigInteger(c).toString(16));
  } catch (UnsupportedEncodingException e) {
    e.printStackTrace();
  }
}

private static void test() {
  Pair<RSAPublicKey, RSAPrivateKey> pair = RSAUtils.genKeyPair(RAS_KEY_SIZE);
  //生成公钥和私钥
  RSAPublicKey publicKey = pair.key;
  RSAPrivateKey privateKey = pair.value;
  //模
  String modulus = publicKey.getModulus().toString();
  //公钥指数
  String public_exponent = publicKey.getPublicExponent().toString();
  //私钥指数
  String private_exponent = privateKey.getPrivateExponent().toString();
  //明文
  byte[] ming = "123456789".getBytes(Constants.UTF_8);
  System.out.println("明文：" + new String(ming, Constants.UTF_8));
  //使用模和指数生成公钥和私钥
  RSAPrivateKey priKey = RSAUtils.getPrivateKey(modulus, private_exponent);
  RSAPublicKey pubKey = RSAUtils.getPublicKey(modulus, public_exponent);
  System.out.println("privateKey=" + priKey);
  System.out.println("publicKey=" + pubKey);
  //加密后的密文
  byte[] mi = RSAUtils.encryptByPublicKey(ming, pubKey);
  System.out.println("密文：" + new String(mi, Constants.UTF_8));
  //解密后的明文
  ming = RSAUtils.decryptByPrivateKey(mi, priKey);
  System.out.println("解密：" + new String(ming, Constants.UTF_8));
}

 Random random = new SecureRandom();
String token = new BigInteger(130, random).toString(32);

private static String digest(final String value) {
  if (MD5 == null) {
    return null;
  }
  byte[] bytes;
  try {
    bytes = value.getBytes(CHARSET);
  } catch (UnsupportedEncodingException e) {
    return null;
  }
  synchronized (MD5) {
    MD5.reset();
    bytes = MD5.digest(bytes);
  }
  String hashed = new BigInteger(1, bytes).toString(16);
  int padding = HASH_LENGTH - hashed.length();
  if (padding == 0) {
    return hashed;
  }
  char[] zeros = new char[padding];
  Arrays.fill(zeros, '0');
  return String.valueOf(zeros) + hashed;
}

private static String calcClassSign(String name) {
  try {
    Class<?> clazz = Class.forName(name);
    ByteArrayOutputStream result = new ByteArrayOutputStream();
    ObjectOutputStream outputStream = new ObjectOutputStream(result);
    outputStream.writeObject(clazz);
    outputStream.close();
    MessageDigest crypt = MessageDigest.getInstance("SHA-1");
    crypt.reset();
    crypt.update(result.toByteArray());
    return new BigInteger(1, crypt.digest()).toString(16);
  } catch (Exception e) {
    throw new IllegalStateException("Can't calculate sign of " + name, e);
  }
}

RSAPublicKeySpec rsaPubKS = new RSAPublicKeySpec(new BigInteger(big1, 16), new BigInteger(big2, 16));
KeyFactory kf = KeyFactory.getInstance("RSA");
RSAPublicKey publicKey = (RSAPublicKey) kf.generatePublic(rsaPubKS);
String modulus = publicKey.getModulus().toString();
String public_exponent = publicKey.getPublicExponent().toString();
System.err.println(modulus);
System.err.println(public_exponent);
System.err.println(mi);

@Test
public void blockTest() {
  String rlp = "f90498f90490f90217a0887405e8cf98cfdbbf5ab4521d45a0803e397af61852d94dc46ca077787088bfa0d6d234f05ac90931822b7b6f244cef81" +
      "83e5dd3080483273d6c2fcc02399216294ee0250c19ad59305b2bdb61f34b45b72fe37154fa0caa558a47a66b975426c6b963c46bb83d969787cfedc09fd2cab8ab83155568da07c970ab3f2004e2aa0" +
      "7d7b3dda348a3a4f8f4ab98b3504c46c1ffae09ef5bd23a077007d3a4c7c88823e9f80b1ba48ec74f88f40e9ec9c5036235fc320fe8a29ffb90100000000000000000000000000000000000000000000" +
      "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" +
      "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" +
      "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000008311fc6782" +
      "02868508cc8cac48825208845682c3479ad983010302844765746887676f312e352e318777696e646f7773a020269a7f434e365b012659d1b190aa1586c22d7bbf0ed7fad73ca7d2b60f623c8841c814" +
      "3ae845fb3df867f8656e850ba43b7400830fffff9431e2e1ed11951c7091dfba62cd4b7145e947219c4d801ba0ad82686ee482723f88d9760b773e7b8234f126271e53369b928af0cbab302baea04fe3" +
      "dd2e0dbcc5d53123fe49f3515f0844c7e4c6dd3752f0cf916f4bb5cbe80bf9020af90207a08752c2c47c96537cf695bdecc9696a8ea35b6bfdc1389a134b47ad63fea38c2ca01dcc4de8dec75d7aab85" +
      "b567b6ccd41ad312451b948a7413f0a142fd40d493479450b8f981ce93fd5b81b844409169148428400bf3a05bff1dc620da4d3a123f8e08536434071281d64fc106105fb3bc94b6b1b8913ba0b59542" +
      "42bb4483396ae474b02651b40d4a9d61ab99a7455e57ef31f2688bdf81a03068c58706501d3059f40a5366debf4bf1cad48439d19f00154076c5d96c26d6b90100000000000000000000000000000000" +
      "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" +
      "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" +
      "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" +
      "008311f7ea8202848508d329637f825208845682c3438acccccccccccccccccccca0216ef6369d46fe0ad70d2b7f9aa0785f33cbb8894733859136b5143c0ed8b09f88bc45a9ac8c1cea67842b0113c6";
  NewBlockMessage msg = new NewBlockMessage(Hex.decode(rlp));
  Block b = msg.getBlock();
  System.out.println(b);
  System.out.println(msg.getDifficultyAsBigInt().toString(16));
}

public String secureRandomString() {
  return new BigInteger(130, random).toString(Character.MAX_RADIX);
}

public @CheckForNull
String getHash(String sourceFile) {
  StringBuilder rawHash = hashes.get(sourceFile);
  if (rawHash == null || digest == null) {
    return null;
  }
  byte[] data = digest.digest(UTF8.getBytes(rawHash.toString()));
  String tmp = new BigInteger(1, data).toString(16);
  if (tmp.length() < 32) {
    tmp = "000000000000000000000000000000000".substring(0, 32 - tmp.length()) + tmp;
  }
  return tmp;
}

private static String calcClassSign(String name) {
  try {
    Class<?> clazz = Class.forName(name);
    ByteArrayOutputStream result = new ByteArrayOutputStream();
    ObjectOutputStream outputStream = new ObjectOutputStream(result);
    outputStream.writeObject(clazz);
    outputStream.close();
    MessageDigest crypt = MessageDigest.getInstance("SHA-1");
    crypt.reset();
    crypt.update(result.toByteArray());
    return new BigInteger(1, crypt.digest()).toString(16);
  } catch (Exception e) {
    throw new IllegalStateException("Can't calculate sign of " + name, e);
  }
}

@Test
public void encodeTest1() {
  StandaloneBlockchain sb = new StandaloneBlockchain().withAutoblock(true);
  SolidityContract a = sb.submitNewContract(
      "contract A {" +
          "  int public a;" +
          "  function f(int a_) {a = a_;}" +
          "}");
  a.callFunction("f", "ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff");
  BigInteger r = (BigInteger) a.callConstFunction("a")[0];
  System.out.println(r.toString(16));
  Assert.assertEquals(new BigInteger(Hex.decode("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff")), r);
}

  public String nextSessionId() {
    return new BigInteger(50, random).toString(16);
  }
}

private static String calcClassSign(String name) {
  try {
    Class<?> clazz = Class.forName(name);
    ByteArrayOutputStream result = new ByteArrayOutputStream();
    ObjectOutputStream outputStream = new ObjectOutputStream(result);
    outputStream.writeObject(clazz);
    outputStream.close();
    MessageDigest crypt = MessageDigest.getInstance("SHA-1");
    crypt.reset();
    crypt.update(result.toByteArray());
    return new BigInteger(1, crypt.digest()).toString(16);
  } catch (Exception e) {
    throw new IllegalStateException("Can't calculate sign of " + name, e);
  }
}

@Test
public void encodeTest2() {
  StandaloneBlockchain sb = new StandaloneBlockchain().withAutoblock(true);
  SolidityContract a = sb.submitNewContract(
      "contract A {" +
          "  uint public a;" +
          "  function f(uint a_) {a = a_;}" +
      "}");
  a.callFunction("f", "ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff");
  BigInteger r = (BigInteger) a.callConstFunction("a")[0];
  System.out.println(r.toString(16));
  Assert.assertEquals(new BigInteger(1, Hex.decode("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff")), r);
}

Javadoc

Returns a string representation of this BigInteger in decimal form.

Popular methods of BigInteger

<init>
This internal constructor differs from its public cousin with the arguments reversed in two ways: it
valueOf
Returns a BigInteger with the given two's complement representation. Assumes that the input array wi
compareTo
Compares this BigInteger with value. Returns -1if this < value, 0 if this == value and 1if this > va
longValue
Returns this BigInteger as a long value. If this is too big to be represented as a long, then this %
add
Adds the contents of the int arrays x and y. This method allocates a new int array to hold the answe
intValue
Converts this BigInteger to an int. This conversion is analogous to a narrowing primitive conversion
toByteArray
Returns the two's complement representation of this BigInteger in a byte array.
equals
Compares this BigInteger with the specified Object for equality.
multiply
Returns a BigInteger whose value is this * value.
subtract
Subtracts the contents of the second int arrays (little) from the first (big). The first int array (
bitLength
Calculate bitlength of contents of the first len elements an int array, assuming there are no leadin
divide
Returns a BigInteger whose value is this / divisor.

Popular in Java

Running tasks concurrently on multiple threads
scheduleAtFixedRate (ScheduledExecutorService)
getSharedPreferences (Context)
compareTo (BigDecimal)
Compares this BigDecimal with the specified BigDecimal. Two BigDecimal objects that are equal in val
GridBagLayout (java.awt)
The GridBagLayout class is a flexible layout manager that aligns components vertically and horizonta
BufferedWriter (java.io)
Wraps an existing Writer and buffers the output. Expensive interaction with the underlying reader is
HashMap (java.util)
HashMap is an implementation of Map. All optional operations are supported.All elements are permitte
Callable (java.util.concurrent)
A task that returns a result and may throw an exception. Implementors define a single method with no
XPath (javax.xml.xpath)
XPath provides access to the XPath evaluation environment and expressions. Evaluation of XPath Expr
Logger (org.apache.log4j)
This is the central class in the log4j package. Most logging operations, except configuration, are d

How to use toStringmethodin java.math.BigInteger

Best Java code snippets using java.math.BigInteger.toString (Showing top 20 results out of 13,761)

Refine search

How to use
toString
method
in
java.math.BigInteger