import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
/**
* Created by xn on 15/7/22.
*/
public class ListUtil {
/**
* 在list中匹配出值为value的项
* @param list
* @param value
* @param <T>
* @return
*/
public static <T> T matchObject(List<T> list,T value) {
if(list == null || list.size() == 0 || value == null){
return null;
}
for(T t : list) {
if(value.equals(t)){
return t;
}
}
return null;
}
/**
* 在list中匹配出T中id属性值为id的项
* @param list
* @param id
* @param <T>
* @return
*/
public static <T> T matchObject(List<T> list,Long id) {
if(list == null || list.size() == 0 || id == null){
return null;
}
Class clazz = list.get(0).getClass();
Method method = null;
try {
method = clazz.getMethod("getId");
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
for(T t : list) {
try {
if(id.equals(method.invoke(t))){
return t;
}
} catch (IllegalAccessException | InvocationTargetException e) {
e.printStackTrace();
}
}
return null;
}
/**
* 在list中匹配出T中fieldName属性值为id的项
* @param list
* @param fieldName
* @param id
* @param <T>
* @param <K>
* @return
*/
public static <T,K> T matchObject(List<T> list,String fieldName,K id) {
if(list == null || list.size() == 0 || id == null){
return null;
}
Class clazz = list.get(0).getClass();
Method method = null;
try {
method = clazz.getMethod("get" + upperFirstWord(fieldName));
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
for(T t : list) {
try {
if(id.equals(method.invoke(t))){
return t;
}
} catch (IllegalAccessException | InvocationTargetException e) {
e.printStackTrace();
}
}
return null;
}
/**
* 在list中匹配出T中fieldName属性值在ids中的项
* @param list
* @param fieldName
* @param ids
* @param <T>
* @param <K>
* @return
*/
public static <T,K> List<T> matchBatchObject(List<T> list,String fieldName,List<K> ids) {
List<T> result = new ArrayList();
if(list == null || list.size() == 0 || ids == null || ids.size() == 0){
return result;
}
Class clazz = list.get(0).getClass();
Method method = null;
try {
method = clazz.getMethod("get" + upperFirstWord(fieldName));
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
for(K id :ids){
for(T t : list) {
try {
if(id.equals(method.invoke(t))){
result.add(t);
break;
}
} catch (IllegalAccessException | InvocationTargetException e) {
e.printStackTrace();
}
}
}
return result;
}
/**
* 在list中匹配出T中id属性值在ids中的项
* @param list
* @param ids
* @param <T>
* @return
*/
public static <T> List<T> matchBatchObject(List<T> list,List<Long> ids) {
List<T> result = new ArrayList();
if(list == null || list.size() == 0 || ids == null || ids.size() == 0){
return result;
}
Class clazz = list.get(0).getClass();
Method method = null;
try {
method = clazz.getMethod("getId");
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
for(Long id :ids){
for(T t : list) {
try {
if(id.equals(method.invoke(t))){
result.add(t);
break;
}
} catch (IllegalAccessException | InvocationTargetException e) {
e.printStackTrace();
}
}
}
return result;
}
/**
* 在list中匹配出T中id属性值为id的集合
* @param list
* @param id
* @param <T>
* @return
*/
public static <T> List<T> matchList(List<T> list,Long id) {
List<T> result = new ArrayList();
if(list == null || list.size() == 0 || id == null){
return result;
}
Class clazz = list.get(0).getClass();
Method method = null;
try {
method = clazz.getMethod("getId");
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
for(T t : list) {
try {
if(id.equals(method.invoke(t))){
result.add(t);
}
} catch (IllegalAccessException | InvocationTargetException e) {
e.printStackTrace();
}
}
return result;
}
/**
* 在list中匹配出T中id属性值在ids中的集合
* @param list
* @param ids
* @param <T>
* @return
*/
public static <T> List<T> matchList(List<T> list,List<Long> ids) {
List<T> result = new ArrayList();
if(list == null || list.size() == 0 || ids == null || ids.size() == 0){
return result;
}
Class clazz = list.get(0).getClass();
Method method = null;
try {
method = clazz.getMethod("getId");
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
for(Long id : ids){
for(T t : list) {
try {
if(id.equals(method.invoke(t))){
result.add(t);
}
} catch (IllegalAccessException | InvocationTargetException e) {
e.printStackTrace();
}
}
}
return result;
}
/**
* 在list中匹配出T中fieldName属性值为id的集合
* @param list
* @param fieldName
* @param id
* @param <T>
* @param <K>
* @return
*/
public static <T,K> List<T> matchList(List<T> list,String fieldName,K id) {
List<T> result = new ArrayList();
if(list == null || list.size() == 0 || id == null){
return result;
}
Class clazz = list.get(0).getClass();
Method method = null;
try {
method = clazz.getMethod("get" + upperFirstWord(fieldName));
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
for(T t : list) {
try {
if(id.equals(method.invoke(t))){
result.add(t);
}
} catch (IllegalAccessException | InvocationTargetException e) {
e.printStackTrace();
}
}
return result;
}
/**
* 在list中匹配出T中fieldName属性值在ids的集合
* @param list
* @param fieldName
* @param ids
* @param <T>
* @param <K>
* @return
*/
public static <T,K> List<T> matchList(List<T> list,String fieldName,List<K> ids) {
List<T> result = new ArrayList();
if(list == null || list.size() == 0 || ids == null || ids.size() == 0){
return result;
}
Class clazz = list.get(0).getClass();
Method method = null;
try {
method = clazz.getMethod("get" + upperFirstWord(fieldName));
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
for(K id : ids){
for(T t : list) {
try {
if(id.equals(method.invoke(t))){
result.add(t);
}
} catch (IllegalAccessException | InvocationTargetException e) {
e.printStackTrace();
}
}
}
return result;
}
/**
* 获取list的id集合
* @param list
* @param <T>
* @return
*/
public static <T> List<Long> getKeyList(List<T> list) {
List<Long> result = new ArrayList();
if(list == null || list.size() == 0){
return result;
}
Class clazz = list.get(0).getClass();
Method method = null;
try {
method = clazz.getMethod("getId");
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
Set<Long> set = new HashSet<>();
for(T t : list) {
try {
Long id = (Long)method.invoke(t);
if(id != null){
set.add(id);
}
} catch (IllegalAccessException | InvocationTargetException e) {
e.printStackTrace();
}
}
for(Long id : set){
result.add(id);
}
return result;
}
/**
* 获取list中fieldName属性值集合
* @param list
* @param fieldName
* @param <T>
* @param <K>
* @return
*/
public static <T,K> List<K> getKeyList(List<T> list,String fieldName) {
List<K> result = new ArrayList();
if(list == null || list.size() == 0){
return result;
}
Class clazz = list.get(0).getClass();
Method method = null;
try {
method = clazz.getMethod("get" + upperFirstWord(fieldName));
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
Set<K> set = new HashSet<>();
for(T t : list) {
try {
K k = (K)method.invoke(t);
if(k != null){
set.add(k);
}
} catch (IllegalAccessException | InvocationTargetException e) {
e.printStackTrace();
}
}
for(K k : set){
result.add(k);
}
return result;
}
/**
* 将list中对象类型转换为T类型
* @param list
* @param clazz
* @param <T>
* @param <K>
* @return
*/
public static <T,K> List<T> transferBatch(List<K> list, Class<T> clazz){
List<T> tList = new ArrayList<>();
for(K k : list){
T t = transfer(k,clazz);
tList.add(t);
}
return tList;
}
/**
* 首字符转大写
* @param str
* @return
*/
public static String upperFirstWord(String str) {
String temp = str.substring(0, 1);
return temp.toUpperCase() + str.substring(1);
}
/**
* 将对象转化为指定类型对象
* @param object
* @param clazz
* @param <T>
* @return
*/
public static <T> T transfer(Object object, Class<T> clazz) {
JSONObject obj = JSON.parseObject(JSON.toJSONString(object));
T t = JSON.toJavaObject(obj, clazz);
return t;
}
}
List操作工具类
猜你喜欢
转载自blog.csdn.net/HXNLYW/article/details/84526326
今日推荐
周排行