今天遇到一个问题，在spring配置文件中的id第二个字母不能大写，否则会产生异常：Bean property 'kManager' is not writable or has an invalid setter method. Did you mean 'KManager'?.为了解决问题研究了一下问题的原因：spring在autoWire的同时用到了jdk提供的java.beans.*目录下的类(等有时间好好研究一下这些类，功能很强大)，通过它们能够得到bean的详细信息。其中有个类PropertyDestriptor类能够通过bean中的set/get方法找到property，不过有个小前提：property的命名要遵循第二个字母不能大写。因为java是国外开发的，它对命名遵循了英语的一个规范：大部分的单词第二个字母都是小写的，除了URL之类的单词。
下面的java.beans.Introspector类中通过set/get方法找到property的代码(希望大家可以自己去看看java.beans.*的代码)。Open Source! I love it.
/**
* Utility method to take a string and convert it to normal Java variable
* name capitalization. This normally means converting the first
* character from upper case to lower case, but in the (unusual) special
* case when there is more than one character and both the first and
* second characters are upper case, we leave it alone.
* <p>
* Thus "FooBah" becomes "fooBah" and "X" becomes "x", but "URL" stays
* as "URL".
*
* @param name The string to be decapitalized.
* @return The decapitalized version of the string.
*/
public static String decapitalize(String name) {
if (name == null || name.length() == 0) {
return name;
}
if (name.length() > 1 && Character.isUpperCase(name.charAt(1)) &&
Character.isUpperCase(name.charAt(0))){
return name;
}
char chars[] = name.toCharArray();
chars[0] = Character.toLowerCase(chars[0]);
return new String(chars);
}