java String 笔试题

1.将一个给定的字符串如 “I am a GOOD People" 的每个单词首字母大写，其它小写，并去掉空格。

/**
 * @author donye
 *
 */
public class CapitalTester {
	public static String capitalEachWord(String source){
		if (source==null||source.equals("")) {
			throw new IllegalArgumentException("字符串为空或空指针");
		}
		String[] splitArr = source.split(" ");
		StringBuilder strBuild = new StringBuilder();
		for (int i = 0; i < splitArr.length; i++) {
			strBuild.append(capitaleFirst(splitArr[i]));
		}
		return strBuild.toString();
	}
	public static String capitaleFirst(String word){
		if (word==null||word.equals("")) {
			throw new IllegalArgumentException("字符串为空或空指针");
		}
	     return Character.toUpperCase(word.charAt(0))+word.substring(1).toLowerCase();
	}
	public static void main(String[] args) {
		String testStr = "A DOg jump FROM the foX";
		String result =CapitalTester.capitalEachWord(testStr);
		System.out.println(result);
	}
}