java反射检测参数的某个字段不能为空

package test;import java.lang.reflect.Method;import java.util.HashMap;import java.util.Map;/** *  * @author 0414 * */public class TestReflectChecker {public class Param {private String id;private String name;private String year;private String month;private String day;public Param() {}public String getDay() {return day;}public void setDay(String day) {this.day = day;}public String getId() {return id;}public void setId(String id) {this.id = id;}public String getMonth() {return month;}public void setMonth(String month) {this.month = month;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getYear() {return year;}public void setYear(String year) {this.year = year;}}/** * CHECK_FIELD */private enum CHECK_FIELD {id,name,year,month,day}private static Map<String, CHECK_FIELD[]> matchMap = new HashMap<String, CHECK_FIELD[]>();static {//id 1 : name is not null;matchMap.put("1",new CHECK_FIELD[] { CHECK_FIELD.id, CHECK_FIELD.name });//id 2 : year, month, day is not null;matchMap.put("2", new CHECK_FIELD[] { CHECK_FIELD.id, CHECK_FIELD.year,CHECK_FIELD.month, CHECK_FIELD.day });}private TestReflectChecker() {}/** * パラメタをチェック *  * @param param * @return */public static boolean check(Param param) {if (param == null) {return false;}String id = param.getId();CHECK_FIELD[] checkFields = matchMap.get(id);if (checkFields == null) {return false;}for (CHECK_FIELD field : checkFields) {Method getFieldMethod = getGetMehtodByField(Param.class, field.toString());try {Object value = getFieldMethod.invoke(param, new Object[] {});if (value == null) {System.out.println(field + " is null, false will be return .");return false;}} catch (Exception e) {e.printStackTrace();return false;}}return true;}/** * fieldからmethodを取得 *  * @param clazz * @param field * @return */private static Method getGetMehtodByField(Class clazz, String field) {Method method = null;String methodName = "get" + field.substring(0, 1).toUpperCase()+ field.substring(1);try {method = clazz.getMethod(methodName, new Class[] {});} catch (Exception e) {e.printStackTrace();}return method;}public static void main(String[] args) {Param param = new TestReflectChecker().new Param();param.setId("1");param.setName("name");System.out.println(TestReflectChecker.check(param));param.setId("2");param.setYear("2011");System.out.println(TestReflectChecker.check(param));}}