字符串可否转化为字符(数组)，如果字符串只有一个字符，如何转化为一个char类型的，谢谢！

能，用getChars()方法：
getChars
public void getChars(int srcBegin,
int srcEnd,
char[] dst,
int dstBegin)Copies characters from this string into the destination character array.
The first character to be copied is at index srcBegin; the last character to be copied is at index srcEnd-1 (thus the total number of characters to be copied is srcEnd-srcBegin). The characters are copied into the subarray of dst starting at index dstBegin and ending at index:

dstbegin + (srcEnd-srcBegin) - 1

Parameters:
srcBegin - index of the first character in the string to copy.
srcEnd - index after the last character in the string to copy.
dst - the destination array.
dstBegin - the start offset in the destination array.
Throws:
IndexOutOfBoundsException - If any of the following is true:
srcBegin is negative.
srcBegin is greater than srcEnd
srcEnd is greater than the length of this string
dstBegin is negative
dstBegin+(srcEnd-srcBegin) is larger than dst.length

在String类当中提供了方法将一个串转化为字符数组！
viod getChar(int srBegin,int srcEnd,char[] dst,int dstBegin) 将字符从此字符串复制到目标字符数组
char[] toCharArray();将次字符串转化为一个新的字符数组。