StringBuilder类codePointCount()方法 (StringBuilder Class codePointCount() method)

• codePointCount() method is available in java.lang package.

  codePointCount()方法在java.lang包中可用。

• codePointCount() method is used to count the number of Unicode code points lies in the given range beg_idx to end_idx.

  codePointCount()方法用于计算从beg_idx到end_idx的给定范围内的Unicode代码点数。

• codePointCount() 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.

  codePointCount()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。

• codePointCount() method may throw an exception at the time of assigning index.

  分配索引时， codePointCount()方法可能会引发异常。

  IndexOutOfBoundsException - This exception may throw when the beg_idx < 0 or end_idx is not less than the length of this array sequence or the other condition is beg_idx > end_idx.

  IndexOutOfBoundsException-当beg_idx <0或end_idx不小于此数组序列的长度或其他条件为beg_idx> end_idx时，可能引发此异常。

Syntax:

句法：

    public int codePointCount(int beg_idx , int end_idx);

Parameter(s):

参数：

• int beg_idx – represents the starting index of Unicode code point to start.

  int beg_idx –表示要开始的Unicode代码点的起始索引。

• int end_idx – represents the ending index of Unicode code point to ends.

  int end_idx –表示Unicode代码指向结尾的结尾索引。

Return value:

返回值：

The return type of this method is int, it returns the counts of the number of Unicode code point of the given range.

此方法的返回类型为int ，它返回给定范围的Unicode代码点的数量的计数。

Example:

例：

// Java program to demonstrate the example 
// of int codePointCount(int beg_idx , int end_idx)
// method of StringBuilder 
public class CodePointCount {
public static void main(String[] args) {
// Creating an StringBuilder object
StringBuilder st_b = new StringBuilder("Java World");
System.out.println("st_b = " + st_b);
// By using codePointCount(4,8) method is to count the 
// number of codepoint lies in a range from index 4 
// to index 8
int cp = st_b.codePointCount(4, 8);
// Display all the codepoints from index 4 to index 8
System.out.println("st_b.codePointCount(4,8) = " + cp);
}
}

Output

输出量

st_b = Java World
st_b.codePointCount(4,8) = 4

翻译自: https://www.includehelp.com/java/stringbuilder-codepointcount-method-with-example.aspx