使用java反射机制对类字段进行选择性校验示例
2016-03-11 16:44
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这是一个使用java反射机制对类字段进行校验的工具，在工厂类中定义map存储需要校验的类类型和该类中需要校验的字段，在校验类中使用反射获取相关类的字段并进行校验，多用于接口开发时对字段的校验。
1、定义三个常用类用于测试
package validation;
//测试用的动物类
public class Animal {
private String animalName;
private String animalColor;
public String getAnimalName() {
return animalName;
}
public void setAnimalName(String animalName) {
this.animalName = animalName;
}
public String getAnimalColor() {
return animalColor;
}
public void setAnimalColor(String animalColor) {
this.animalColor = animalColor;
}
}
package validation;
//测试用的水果类
public class Fruit {
private String fruitKind;
private String fruitColor;
private String fruitAmount;
public String getFruitKind() {
return fruitKind;
}
public void setFruitKind(String fruitKind) {
this.fruitKind = fruitKind;
}
public String getFruitColor() {
return fruitColor;
}
public void setFruitColor(String fruitColor) {
this.fruitColor = fruitColor;
}
public String getFruitamount() {
return fruitAmount;
}
public void setFruitamount(String fruitamount) {
this.fruitAmount = fruitamount;
}
}
package validation;
//测试用的人物类
public class Person {
private String personName;
private String personSex;
private String personAge;
public String getPersonName() {
return personName;
}
public void setPersonName(String personName) {
this.personName = personName;
}
public String getPersonSex() {
return personSex;
}
public void setPersonSex(String personSex) {
this.personSex = personSex;
}
public String getPersonAge() {
return personAge;
}
public void setPersonAge(String personAge) {
this.personAge = personAge;
}
}
二、使用工厂类初始化需要校验的类和字段有哪些
package validation;
import java.util.HashMap;
import java.util.Map;
/**
* 注入需要校验的类类型的工厂类
*
*/
public class ValidationDataMapFactory {
private Map<String, Map<String, String>> beanTransationMap;
private static ValidationDataMapFactory validationDataMapFactory;
//使用构造方法初始化所需Map,在对象被创建时初始化
public ValidationDataMapFactory(){
initBeanTransationMap();
}
//单例模式初始化对象
public static ValidationDataMapFactory newInstance(){
if(validationDataMapFactory == null){
validationDataMapFactory = new ValidationDataMapFactory();
}
return validationDataMapFactory;
}
public Map<String, Map<String, String>> getBeanTransationMap(){
return this.beanTransationMap;
}
//初始化map，用于存储哪些类和字段需要校验
private void initBeanTransationMap(){
if(beanTransationMap == null){
this.beanTransationMap = new HashMap<String, Map<String,String>>();
}
this.beanTransationMap.put(Person.class.getName(), addPersonTransationMap());
this.beanTransationMap.put(Animal.class.getName(), addAnimalTransationMap());
this.beanTransationMap.put(Fruit.class.getName(), addFruitTransationMap());
}
private Map<String, String> addPersonTransationMap(){
Map<String, String> personTransationMap = new HashMap<String, String>();
personTransationMap.put("personName", "人员名称");
personTransationMap.put("personAge", "人员年龄");
return personTransationMap;
}
private Map<String, String> addAnimalTransationMap(){
Map<String, String> animalTransationMap = new HashMap<String, String>();
animalTransationMap.put("animalName", "动物名");
animalTransationMap.put("animalColor", "动物颜色");
return animalTransationMap;
}
private Map<String, String> addFruitTransationMap(){
Map<String, String> fruitTransationMap = new HashMap<String, String>();
fruitTransationMap.put("fruitKind", "水果种类");
fruitTransationMap.put("fruitAmount", "水果数量");
return fruitTransationMap;
}
}
三、使用反射获取需要校验的类的字段进行校验
package validation;
import java.lang.reflect.Field;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
/**
* 校验规则类
*/
public class ValidationEmptyData {
/**校验bean字段中文转义map**/
private Map<String, Map<String, String>> beanTransationMap;
public ValidationEmptyData(Map<String,Map<String, String>> beanTransationMap){
this.beanTransationMap = beanTransationMap;
}
/**
* 校验自定义的并且需要校验的javaBean中的字段不能为空
* @param bean 要进行校验的javaBean
* @throws Exception
* @throws
*/
@SuppressWarnings("rawtypes")
public void validationEmptyData(Object bean) throws Exception{
Class clazz = bean.getClass();
if(haveValidation(clazz)){
validationBeanField(clazz.getDeclaredFields(), bean, clazz);
}
}
/**
* 校验bean中的字段
* @param fields 属性字段
* @param bean 要进行校验的bean
* @param beanClass 要进行校验bean的Class
* @throws Exception
*/
@SuppressWarnings({ "unchecked", "rawtypes" })
public void validationBeanField(Field[] fields, Object bean, Class beanClass) throws Exception{
Class superClazz = beanClass.getSuperclass();
//获取包括其父类在内的所有字段
if(null != superClazz && haveValidation(superClazz)){
validationBeanField(superClazz.getDeclaredFields(),bean, superClazz);
}
Map<String, String> fieldTransationMap = getFieldTransationMap(beanClass.getName());
if(null != fields && fields.length > 0){
for(Field field : fields){
field.setAccessible(true);
String fieldName = field.getName();
Class fieldClass = field.getType();
Object fieldValue = field.get(bean);
if(fieldClass.isAssignableFrom(String.class)){
if(isEmptyString((String)fieldValue)){
throwEmptyException(fieldName,fieldTransationMap);
}
}else if(fieldClass.isArray()){
validationArray(fieldValue,fieldName, fieldTransationMap);
}else if(fieldClass.isAssignableFrom(List.class)){
validationList(fieldValue,fieldName, fieldTransationMap);
}else if(fieldClass.isAssignableFrom(Map.class)){
validationMap(fieldValue,fieldName, fieldTransationMap);
}else{
if(isNullObject(fieldValue)){
throwEmptyException(fieldName,fieldTransationMap);
}
}
}
}
}
/**
* 校验Map中的字段
* @param map
* @param fieldName
* @param fieldTransationMap
* @throws Exception
*/
@SuppressWarnings("rawtypes")
public void validationMap(Object map, String fieldName,Map<String, String> fieldTransationMap) throws Exception{
if(!isNullObject(map) && !(((Map)map).isEmpty())){
Iterator ite = ((Map)map).keySet().iterator();
while(ite.hasNext()){
Object obj = ((Map)map).get(ite.next());
if(null != obj && haveValidation(obj.getClass())){
validationEmptyData(obj);
}else if(null != obj){
validationObject(obj, fieldName, fieldTransationMap);
}
}
}else{
throwEmptyException(fieldName, fieldTransationMap);
}
}
/**
* 校验list中的值
* @param list
* @param fieldName
* @param fieldTransationMap
* @throws Exception
*/
@SuppressWarnings("rawtypes")
public void validationList(Object list, String fieldName, Map<String, String> fieldTransationMap) throws Exception{
if(!isNullObject(list)){
validationArray(((List)list).toArray(),fieldName, fieldTransationMap);
}else{
throwEmptyException(fieldName, fieldTransationMap);
}
}
/**
* 校验数组中的数据
* @param array
* @param fieldName
* @param fieldTransationMap
* @throws Exception
*/
public void validationArray(Object array,String fieldName, Map<String, String> fieldTransationMap) throws Exception{
if(!isNullObject(array) && (0 < ((Object[]) array).length)){
for(Object obj : (Object[]) array){
if(null != obj && haveValidation(obj.getClass())){
validationEmptyData(obj);
}else if(null != obj){
validationObject(obj, fieldName, fieldTransationMap);
}
}
}else{
throwEmptyException(fieldName, fieldTransationMap);
}
}
/**
* 校验非自定义的对象
* @param obj
* @param fieldName
* @param fieldTransationMap
* @throws Exception
*/
@SuppressWarnings({ "rawtypes", "unchecked" })
private void validationObject(Object obj,String fieldName, Map<String, String> fieldTransationMap) throws Exception{
if(null != obj){
Class objClass = obj.getClass();
if(objClass.isAssignableFrom(String.class)){
if(isEmptyString((String)obj)){
throwEmptyException(fieldName,fieldTransationMap);
}
}else if(objClass.isArray()){
validationArray(obj,fieldName, fieldTransationMap);
}else if(objClass.isAssignableFrom(List.class)){
validationList(obj,fieldName, fieldTransationMap);
}else if(objClass.isAssignableFrom(Map.class)){
validationMap(obj,fieldName, fieldTransationMap);
}else{
if(isNullObject(obj)){
throwEmptyException(fieldName,fieldTransationMap);
}
}
}
}
/**
* 抛出不能为空字段的错误提示
* @param fieldName
* @param fieldTransationMap
* @throws Exception
*/
public void throwEmptyException(String fieldName,Map<String, String> fieldTransationMap) throws Exception{
if(null != fieldTransationMap && !fieldTransationMap.isEmpty() && fieldTransationMap.containsKey(fieldName)){
throw new Exception("字段【"+fieldTransationMap.get(fieldName)+"("+fieldName+")"+"】不能为空！");
}
}
/**
* 判断该对象是否需要进行空值的判断
* @param clazz
* @return
* @throws Exception
*/
@SuppressWarnings("rawtypes")
private boolean haveValidation(Class clazz) throws Exception{
String className = clazz.getName();
if(null == this.beanTransationMap || this.beanTransationMap.isEmpty()){
throw new Exception("先初始化字段转义Map");
}else if(this.beanTransationMap.containsKey(className)){
return true;
}else{
return false;
}
}
/**
* 判断字符串是否为空
* @param value
* @return
*/
private boolean isEmptyString(String value){
if(isNullObject(value) || "".equals(value.trim()) || "null".equals(value.trim())){
return true;
}
return false;
}
/**
* 判断obj对象时是否为null
* @param obj
* @return
*/
private boolean isNullObject(Object obj){
if(null != obj){
return false;
}
return true;
}
/**
* 获得该className所对应的字段中文转义
* @param className
* @return
* @throws Exception
*/
private Map<String, String> getFieldTransationMap(String className) throws Exception{
if(null != this.beanTransationMap && !this.beanTransationMap.isEmpty() && this.beanTransationMap.containsKey(className)){
return this.beanTransationMap.get(className);
}else{
throw new Exception("请为"+className+"添加字段转义Map");
}
}
}
四、进行测试
package validation;
//测试Main类
public class ValidationDataMainTest {
private static ValidationEmptyData validationEmptyData;
public static void main(String[] args) throws Exception {
// Person per = new Person();
// per.setPersonName("kitty");
// per.setPersonSex("nv");
// getValidationEmptyData().validationEmptyData(per);
// Animal ani = new Animal();
// ani.setAnimalName("老虎");
// getValidationEmptyData().validationEmptyData(ani);
Fruit fru = new Fruit();
fru.setFruitKind("香蕉");
getValidationEmptyData().validationEmptyData(fru);
}
public static ValidationEmptyData getValidationEmptyData(){
if(validationEmptyData == null){
ValidationDataMapFactory cvdm = new ValidationDataMapFactory();
validationEmptyData = new ValidationEmptyData(cvdm.getBeanTransationMap());
}
return validationEmptyData;
}
}
1、定义三个常用类用于测试
package validation;
//测试用的动物类
public class Animal {
private String animalName;
private String animalColor;
public String getAnimalName() {
return animalName;
}
public void setAnimalName(String animalName) {
this.animalName = animalName;
}
public String getAnimalColor() {
return animalColor;
}
public void setAnimalColor(String animalColor) {
this.animalColor = animalColor;
}
}
package validation;
//测试用的水果类
public class Fruit {
private String fruitKind;
private String fruitColor;
private String fruitAmount;
public String getFruitKind() {
return fruitKind;
}
public void setFruitKind(String fruitKind) {
this.fruitKind = fruitKind;
}
public String getFruitColor() {
return fruitColor;
}
public void setFruitColor(String fruitColor) {
this.fruitColor = fruitColor;
}
public String getFruitamount() {
return fruitAmount;
}
public void setFruitamount(String fruitamount) {
this.fruitAmount = fruitamount;
}
}
package validation;
//测试用的人物类
public class Person {
private String personName;
private String personSex;
private String personAge;
public String getPersonName() {
return personName;
}
public void setPersonName(String personName) {
this.personName = personName;
}
public String getPersonSex() {
return personSex;
}
public void setPersonSex(String personSex) {
this.personSex = personSex;
}
public String getPersonAge() {
return personAge;
}
public void setPersonAge(String personAge) {
this.personAge = personAge;
}
}
二、使用工厂类初始化需要校验的类和字段有哪些
package validation;
import java.util.HashMap;
import java.util.Map;
/**
* 注入需要校验的类类型的工厂类
*
*/
public class ValidationDataMapFactory {
private Map<String, Map<String, String>> beanTransationMap;
private static ValidationDataMapFactory validationDataMapFactory;
//使用构造方法初始化所需Map,在对象被创建时初始化
public ValidationDataMapFactory(){
initBeanTransationMap();
}
//单例模式初始化对象
public static ValidationDataMapFactory newInstance(){
if(validationDataMapFactory == null){
validationDataMapFactory = new ValidationDataMapFactory();
}
return validationDataMapFactory;
}
public Map<String, Map<String, String>> getBeanTransationMap(){
return this.beanTransationMap;
}
//初始化map，用于存储哪些类和字段需要校验
private void initBeanTransationMap(){
if(beanTransationMap == null){
this.beanTransationMap = new HashMap<String, Map<String,String>>();
}
this.beanTransationMap.put(Person.class.getName(), addPersonTransationMap());
this.beanTransationMap.put(Animal.class.getName(), addAnimalTransationMap());
this.beanTransationMap.put(Fruit.class.getName(), addFruitTransationMap());
}
private Map<String, String> addPersonTransationMap(){
Map<String, String> personTransationMap = new HashMap<String, String>();
personTransationMap.put("personName", "人员名称");
personTransationMap.put("personAge", "人员年龄");
return personTransationMap;
}
private Map<String, String> addAnimalTransationMap(){
Map<String, String> animalTransationMap = new HashMap<String, String>();
animalTransationMap.put("animalName", "动物名");
animalTransationMap.put("animalColor", "动物颜色");
return animalTransationMap;
}
private Map<String, String> addFruitTransationMap(){
Map<String, String> fruitTransationMap = new HashMap<String, String>();
fruitTransationMap.put("fruitKind", "水果种类");
fruitTransationMap.put("fruitAmount", "水果数量");
return fruitTransationMap;
}
}
三、使用反射获取需要校验的类的字段进行校验
package validation;
import java.lang.reflect.Field;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
/**
* 校验规则类
*/
public class ValidationEmptyData {
/**校验bean字段中文转义map**/
private Map<String, Map<String, String>> beanTransationMap;
public ValidationEmptyData(Map<String,Map<String, String>> beanTransationMap){
this.beanTransationMap = beanTransationMap;
}
/**
* 校验自定义的并且需要校验的javaBean中的字段不能为空
* @param bean 要进行校验的javaBean
* @throws Exception
* @throws
*/
@SuppressWarnings("rawtypes")
public void validationEmptyData(Object bean) throws Exception{
Class clazz = bean.getClass();
if(haveValidation(clazz)){
validationBeanField(clazz.getDeclaredFields(), bean, clazz);
}
}
/**
* 校验bean中的字段
* @param fields 属性字段
* @param bean 要进行校验的bean
* @param beanClass 要进行校验bean的Class
* @throws Exception
*/
@SuppressWarnings({ "unchecked", "rawtypes" })
public void validationBeanField(Field[] fields, Object bean, Class beanClass) throws Exception{
Class superClazz = beanClass.getSuperclass();
//获取包括其父类在内的所有字段
if(null != superClazz && haveValidation(superClazz)){
validationBeanField(superClazz.getDeclaredFields(),bean, superClazz);
}
Map<String, String> fieldTransationMap = getFieldTransationMap(beanClass.getName());
if(null != fields && fields.length > 0){
for(Field field : fields){
field.setAccessible(true);
String fieldName = field.getName();
Class fieldClass = field.getType();
Object fieldValue = field.get(bean);
if(fieldClass.isAssignableFrom(String.class)){
if(isEmptyString((String)fieldValue)){
throwEmptyException(fieldName,fieldTransationMap);
}
}else if(fieldClass.isArray()){
validationArray(fieldValue,fieldName, fieldTransationMap);
}else if(fieldClass.isAssignableFrom(List.class)){
validationList(fieldValue,fieldName, fieldTransationMap);
}else if(fieldClass.isAssignableFrom(Map.class)){
validationMap(fieldValue,fieldName, fieldTransationMap);
}else{
if(isNullObject(fieldValue)){
throwEmptyException(fieldName,fieldTransationMap);
}
}
}
}
}
/**
* 校验Map中的字段
* @param map
* @param fieldName
* @param fieldTransationMap
* @throws Exception
*/
@SuppressWarnings("rawtypes")
public void validationMap(Object map, String fieldName,Map<String, String> fieldTransationMap) throws Exception{
if(!isNullObject(map) && !(((Map)map).isEmpty())){
Iterator ite = ((Map)map).keySet().iterator();
while(ite.hasNext()){
Object obj = ((Map)map).get(ite.next());
if(null != obj && haveValidation(obj.getClass())){
validationEmptyData(obj);
}else if(null != obj){
validationObject(obj, fieldName, fieldTransationMap);
}
}
}else{
throwEmptyException(fieldName, fieldTransationMap);
}
}
/**
* 校验list中的值
* @param list
* @param fieldName
* @param fieldTransationMap
* @throws Exception
*/
@SuppressWarnings("rawtypes")
public void validationList(Object list, String fieldName, Map<String, String> fieldTransationMap) throws Exception{
if(!isNullObject(list)){
validationArray(((List)list).toArray(),fieldName, fieldTransationMap);
}else{
throwEmptyException(fieldName, fieldTransationMap);
}
}
/**
* 校验数组中的数据
* @param array
* @param fieldName
* @param fieldTransationMap
* @throws Exception
*/
public void validationArray(Object array,String fieldName, Map<String, String> fieldTransationMap) throws Exception{
if(!isNullObject(array) && (0 < ((Object[]) array).length)){
for(Object obj : (Object[]) array){
if(null != obj && haveValidation(obj.getClass())){
validationEmptyData(obj);
}else if(null != obj){
validationObject(obj, fieldName, fieldTransationMap);
}
}
}else{
throwEmptyException(fieldName, fieldTransationMap);
}
}
/**
* 校验非自定义的对象
* @param obj
* @param fieldName
* @param fieldTransationMap
* @throws Exception
*/
@SuppressWarnings({ "rawtypes", "unchecked" })
private void validationObject(Object obj,String fieldName, Map<String, String> fieldTransationMap) throws Exception{
if(null != obj){
Class objClass = obj.getClass();
if(objClass.isAssignableFrom(String.class)){
if(isEmptyString((String)obj)){
throwEmptyException(fieldName,fieldTransationMap);
}
}else if(objClass.isArray()){
validationArray(obj,fieldName, fieldTransationMap);
}else if(objClass.isAssignableFrom(List.class)){
validationList(obj,fieldName, fieldTransationMap);
}else if(objClass.isAssignableFrom(Map.class)){
validationMap(obj,fieldName, fieldTransationMap);
}else{
if(isNullObject(obj)){
throwEmptyException(fieldName,fieldTransationMap);
}
}
}
}
/**
* 抛出不能为空字段的错误提示
* @param fieldName
* @param fieldTransationMap
* @throws Exception
*/
public void throwEmptyException(String fieldName,Map<String, String> fieldTransationMap) throws Exception{
if(null != fieldTransationMap && !fieldTransationMap.isEmpty() && fieldTransationMap.containsKey(fieldName)){
throw new Exception("字段【"+fieldTransationMap.get(fieldName)+"("+fieldName+")"+"】不能为空！");
}
}
/**
* 判断该对象是否需要进行空值的判断
* @param clazz
* @return
* @throws Exception
*/
@SuppressWarnings("rawtypes")
private boolean haveValidation(Class clazz) throws Exception{
String className = clazz.getName();
if(null == this.beanTransationMap || this.beanTransationMap.isEmpty()){
throw new Exception("先初始化字段转义Map");
}else if(this.beanTransationMap.containsKey(className)){
return true;
}else{
return false;
}
}
/**
* 判断字符串是否为空
* @param value
* @return
*/
private boolean isEmptyString(String value){
if(isNullObject(value) || "".equals(value.trim()) || "null".equals(value.trim())){
return true;
}
return false;
}
/**
* 判断obj对象时是否为null
* @param obj
* @return
*/
private boolean isNullObject(Object obj){
if(null != obj){
return false;
}
return true;
}
/**
* 获得该className所对应的字段中文转义
* @param className
* @return
* @throws Exception
*/
private Map<String, String> getFieldTransationMap(String className) throws Exception{
if(null != this.beanTransationMap && !this.beanTransationMap.isEmpty() && this.beanTransationMap.containsKey(className)){
return this.beanTransationMap.get(className);
}else{
throw new Exception("请为"+className+"添加字段转义Map");
}
}
}
四、进行测试
package validation;
//测试Main类
public class ValidationDataMainTest {
private static ValidationEmptyData validationEmptyData;
public static void main(String[] args) throws Exception {
// Person per = new Person();
// per.setPersonName("kitty");
// per.setPersonSex("nv");
// getValidationEmptyData().validationEmptyData(per);
// Animal ani = new Animal();
// ani.setAnimalName("老虎");
// getValidationEmptyData().validationEmptyData(ani);
Fruit fru = new Fruit();
fru.setFruitKind("香蕉");
getValidationEmptyData().validationEmptyData(fru);
}
public static ValidationEmptyData getValidationEmptyData(){
if(validationEmptyData == null){
ValidationDataMapFactory cvdm = new ValidationDataMapFactory();
validationEmptyData = new ValidationEmptyData(cvdm.getBeanTransationMap());
}
return validationEmptyData;
}
}
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