BigInteger类shiftLeft()方法 (BigInteger Class shiftLeft() method)

• shiftLeft() method is available in java.math package.

  shiftLeft()方法在java.math包中可用。

• shiftLeft() method is used to shift the given number of bits towards the left side in this BigInteger.

  shiftLeft()方法用于将给定数量的位向此BigInteger中的左侧移动。

• shiftLeft() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.

  shiftLeft()方法是一种非静态方法，只能通过类对象访问，如果尝试使用类名称访问该方法，则会收到错误消息。

• shiftLeft() method may throw an exception at the time of shifting bits.

  shiftLeft()方法在移位位时可能会引发异常。

  ArithmeticException: This exception may throw when the given parameter value holds Integer.MIN_VALUE.

  ArithmeticException ：当给定参数值包含Integer.MIN_VALUE时，可能引发此异常。

Syntax:

句法：

    public BigInteger shiftLeft(int number);

Parameter(s):

参数：

• int number – represents the value in bits and when it holds negative value it performs right shift instead of left.

  int number –表示以位为单位的值，当它保持负值时，它执行右移而不是左移。

Return value:

返回值：

The return type of this method is BigInteger, it returns BigInteger that holds the value [(this BigInteger) << (number)].

此方法的返回类型为BigInteger ，它返回保存值[(this BigInteger)<<(number)]的BigInteger。

Example:

例：

// Java program to demonstrate the example 
// of BigInteger setBit(int pos) method of BigInteger
import java.math.*;
public class SetBitOfBI {
public static void main(String args[]) {
// Initialize a variable str
String str = "10";
// Initialize a BigInteger object 
BigInteger b_int = new BigInteger(str);
// Display b_int
System.out.println("b_int: " + b_int);
// Display Binary representation of  str 
System.out.println("Binary Representation of 10: 1010 ");
System.out.println();
// Here, this method setBit(int) method is used
// to set the  bit value from "0" to 1" at the
// given indices in this BigInteger
// b_int and the binary representation of b_int
// is 1010 so the bit "1" is set at the given
// indices (0) so the new binary representation
// is 1011 i.e. 11
BigInteger set_bit = b_int.setBit(0);
System.out.println("b_int.setBit(0): " + set_bit);
System.out.println("Binary Representation of 11: 1011 ");
}
}

Output

输出量

b_int: 10
Binary Representation of 10: 1010 b_int.setBit(0): 11
Binary Representation of 11: 1011 

翻译自: https://www.includehelp.com/java/biginteger-shiftleft-method-with-example.aspx