MapUtil从map结构中获取深度的信息

import cn.hutool.core.bean.BeanUtil;
import cn.hutool.core.util.StrUtil;
import com.alibaba.fastjson.JSON;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class MapUtil {
/**
* 获取[]中间的字符
*/
public static Pattern pattern = Pattern.compile("\[(.*?)]");
/**
* 从Map中连续取值,兼容了空指针异常的情况,
* 表达式样例 {l}.[userList]0.password
*
* @param map
深度map
* @param expression 值获取表达式
* @param clazz
返回值的class对象
* @param <T>
泛型
* @return 若没找到或者表达式错误返回空
*/
public static <T> T get(Map<String, Object> map, String expression, Class<T> clazz) {
if (map == null) {
return null;
}
if (StrUtil.isEmpty(expression)) {
return null;
}
Object temp = map;
String[] array = expression.split("\.");
for (int i = 0; i < array.length; i++) {
String s = array[i];
//最后一条数据直接获取返回值
if (i == (array.length - 1)) {
if (temp instanceof Map) {
return clazz.cast(((Map<?, ?>) temp).get(s));
} else if (temp instanceof Collection) {
return null;
} else if (BeanUtil.isBean(temp.getClass())) {
return clazz.cast(BeanUtil.beanToMap(temp).get(s));
} else {
return null;
}
}
//处理Map对象
if (s.startsWith("{") && s.endsWith("}")) {
String param = removeTextAndLastBracket(s);
if (temp instanceof Map) {
temp = ((Map<?, ?>) temp).get(param);
} else if (temp instanceof Collection) {
return null;
} else if (BeanUtil.isBean(temp.getClass())) {
temp = BeanUtil.beanToMap(temp).get(param);
} else {
return null;
}
}
//处理表达式数组
if (s.startsWith("[") && s.contains("]")) {
String key = getParamInArray(s);
String[] paramArray = s.split("]");
if (paramArray.length < 2) {
return null;
}
int index = Integer.parseInt(paramArray[1]);
if (temp instanceof Map) {
temp = ((Map<?, ?>) temp).get(key);
if (temp instanceof Collection) {
Collection<?> collection = (Collection<?>) temp;
if (index >= collection.size()) {
return null;
}
temp = collection.toArray()[index];
} else {
return null;
}
} else if (temp instanceof Collection) {
return null;
} else if (BeanUtil.isBean(temp.getClass())) {
temp = BeanUtil.beanToMap(temp).get(key);
if (temp instanceof Collection) {
Collection<?> collection = (Collection<?>) temp;
if (index >= collection.size()) {
return null;
}
temp = collection.toArray()[index];
} else {
return null;
}
} else {
return null;
}
}
}
return null;
}
/**
* 从Map中取List
* 表达式样例 {m}.{l}.[userList]
*
* @param map
深度map
* @param expression 值获取表达式
* @param clazz
返回值的class对象
* @param <T>
泛型
* @return 若没找到或者表达式错误返回空
*/
@SuppressWarnings("unchecked")
public static <T> List<T> getArrayList(Map<String, Object> map, String expression, Class<T> clazz) {
if (map == null) {
return null;
}
if (StrUtil.isEmpty(expression)) {
return null;
}
Object temp = map;
String[] array = expression.split("\.");
for (int i = 0; i < array.length; i++) {
String s = array[i];
if (i == (array.length - 1)) {
String param = removeTextAndLastBracket(s);
try {
if (temp instanceof Map) {
temp = ((Map<?, ?>) temp).get(param);
if (temp instanceof List) {
if (checkClass((List<?>) temp, clazz)) {
return (List<T>) temp;
} else {
return null;
}
}
} else if (temp instanceof Collection) {
return null;
} else if (BeanUtil.isBean(temp.getClass())) {
temp = BeanUtil.beanToMap(temp).get(param);
if (temp instanceof List) {
if (checkClass((List<?>) temp, clazz)) {
return (List<T>) temp;
} else {
return null;
}
}
} else {
return null;
}
} catch (Exception e) {
return null;
}
}
if (s.startsWith("{") && s.endsWith("}")) {
String param = removeTextAndLastBracket(s);
if (temp instanceof Map) {
temp = ((Map<?, ?>) temp).get(param);
} else if (temp instanceof Collection) {
return null;
} else if (BeanUtil.isBean(temp.getClass())) {
temp = BeanUtil.beanToMap(temp).get(param);
} else {
return null;
}
}
//处理表达式数组
if (s.startsWith("[") && s.contains("]")) {
String key = getParamInArray(s);
String[] paramArray = s.split("]");
if (paramArray.length < 2) {
return null;
}
int index = Integer.parseInt(paramArray[1]);
if (temp instanceof Map) {
temp = ((Map<?, ?>) temp).get(key);
if (temp instanceof Collection) {
Collection<?> collection = (Collection<?>) temp;
if (index >= collection.size()) {
return null;
}
temp = collection.toArray()[index];
} else {
return null;
}
} else if (temp instanceof Collection) {
return null;
} else if (BeanUtil.isBean(temp.getClass())) {
temp = BeanUtil.beanToMap(temp).get(key);
if (temp instanceof Collection) {
Collection<?> collection = (Collection<?>) temp;
if (index >= collection.size()) {
return null;
}
temp = collection.toArray()[index];
} else {
return null;
}
} else {
return null;
}
}
}
return null;
}
private static String removeTextAndLastBracket(String string) {
if (StrUtil.isEmpty(string)) {
return string;
}
StringBuilder str = new StringBuilder(string);
int i = 0;
do {
str.deleteCharAt(i);
i++;
} while (string.equals("("));
str.deleteCharAt(string.length() - 2);
return str.toString();
}
private static String getParamInArray(String s) {
Matcher matcher = pattern.matcher(s);
if (matcher.find()) {
return matcher.group(1);
}
return null;
}
private static <T> boolean checkClass(List<T> list, Class<?> clazz) {
if (list == null || list.size() == 0) {
return false;
}
return list.get(0).getClass().getName().equals(clazz.getName());
}
}

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