• Java StringBuilder codePointBefore()方法

  java lang StringBuilder codePointBefore()方法指定索引之前返回字符(Unicode代码点)。该指数是指范围从1到length()的char值(Unicode代码

• Java StringBuffer codePointBefore()方法

  java lang StringBuffer codePointBefore()法指定索引之前，返回字符(Unicode代码点)。该索引(Unicode代码单元)范围是1到length()的char值

• Java Character codePointBefore()方法

  java lang Character codePointBefore(CharSequenceseq,intindex)返回CharSequence的给定索引前面的代码点。如果在(index-1)的char值在Char

• Java Character codePointBefore()方法

  java lang Character codePointBefore(char[]a,intindex,intstart)返回的字符数组，其中仅可用于数组元素与索引大于或等于start的给定索引

• Java Character codePointBefore()方法

  java lang Character codePointBefore(char[]a,intindex)返回char数组的给定索引前面的代码点。如果在(index-1)的char值的字符数组中是在低