SortListUtil
作者：互联网
package com.huawei.hmnewexperience.util;
import org.springframework.util.CollectionUtils;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Collections;
import java.util.Comparator;
import java.util.Date;
import java.util.List;
/**
* 通用工具类之按对象中某属性排序 *
*/
public class SortListUtil {
public static final String DESC = "desc";
public static final String ASC = "asc";
/**
* 对list中的元素按升序排列.
*
* @param list 排序集合
* @param field 排序字段
* @return
*/
public static List<?> sort(List<?> list, final String field) {
return sort(list, field, null);
}
/**
* 对list中的元素进行排序.
*
* @param list 排序集合
* @param field 排序字段
* @param sort 排序方式: SortList.DESC(降序) SortList.ASC(升序).
* @return
*/
@SuppressWarnings("unchecked")
public static List<?> sort(List<?> list, final String field,
final String sort) {
if (CollectionUtils.isEmpty(list)) {
return list;
}
Collections.sort(list, new Comparator() {
public int compare(Object a, Object b) {
int ret = 0;
try {
Field f = a.getClass().getDeclaredField(field);
f.setAccessible(true);
Class<?> type = f.getType();
if (type == int.class) {
ret = ((Integer) f.getInt(a)).compareTo((Integer) f
.getInt(b));
} else if (type == double.class) {
ret = ((Double) f.getDouble(a)).compareTo((Double) f
.getDouble(b));
} else if (type == long.class) {
ret = ((Long) f.getLong(a)).compareTo((Long) f
.getLong(b));
} else if (type == float.class) {
ret = ((Float) f.getFloat(a)).compareTo((Float) f
.getFloat(b));
} else if (type == Date.class) {
ret = ((Date) f.get(a)).compareTo((Date) f.get(b));
} else if (isImplementsOf(type, Comparable.class)) {
ret = ((Comparable) f.get(a)).compareTo((Comparable) f
.get(b));
} else {
ret = String.valueOf(f.get(a)).compareTo(
String.valueOf(f.get(b)));
}
} catch (SecurityException e) {
e.printStackTrace();
} catch (NoSuchFieldException e) {
e.printStackTrace();
} catch (IllegalArgumentException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
}
if (sort != null && sort.toLowerCase().equals(DESC)) {
return -ret;
} else {
return ret;
}
}
});
return list;
}
/**
* 对list中的元素按fields和sorts进行排序,
* fields[i]指定排序字段,sorts[i]指定排序方式.如果sorts[i]为空则默认按升序排列.
*
* @param list
* @param fields
* @param sorts
* @return
*/
@SuppressWarnings("unchecked")
public static List<?> sort(List<?> list, String[] fields, String[] sorts) {
if (fields != null && fields.length > 0) {
for (int i = fields.length - 1; i >= 0; i--) {
final String field = fields[i];
String tmpSort = ASC;
if (sorts != null && sorts.length > i && sorts[i] != null) {
tmpSort = sorts[i];
}
final String sort = tmpSort;
Collections.sort(list, new Comparator() {
public int compare(Object a, Object b) {
int ret = 0;
try {
Field f = a.getClass().getDeclaredField(field);
f.setAccessible(true);
Class<?> type = f.getType();
if (type == int.class) {
ret = ((Integer) f.getInt(a))
.compareTo((Integer) f.getInt(b));
} else if (type == double.class) {
ret = ((Double) f.getDouble(a))
.compareTo((Double) f.getDouble(b));
} else if (type == long.class) {
ret = ((Long) f.getLong(a)).compareTo((Long) f
.getLong(b));
} else if (type == float.class) {
ret = ((Float) f.getFloat(a))
.compareTo((Float) f.getFloat(b));
} else if (type == Date.class) {
ret = ((Date) f.get(a)).compareTo((Date) f
.get(b));
} else if (isImplementsOf(type, Comparable.class)) {
ret = ((Comparable) f.get(a))
.compareTo((Comparable) f.get(b));
} else {
ret = String.valueOf(f.get(a)).compareTo(
String.valueOf(f.get(b)));
}
} catch (SecurityException e) {
e.printStackTrace();
} catch (NoSuchFieldException e) {
e.printStackTrace();
} catch (IllegalArgumentException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
}
if (sort != null && sort.toLowerCase().equals(DESC)) {
return -ret;
} else {
return ret;
}
}
});
}
}
return list;
}
/**
* 默认按正序排列
*
* @param list
* @param method
* @return
*/
public static List<?> sortByMethod(List<?> list, final String method) {
return sortByMethod(list, method, null);
}
@SuppressWarnings("unchecked")
public static List<?> sortByMethod(List<?> list, final String method,
final String sort) {
Collections.sort(list, new Comparator() {
public int compare(Object a, Object b) {
int ret = 0;
try {
Method m = a.getClass().getMethod(method, null);
m.setAccessible(true);
Class<?> type = m.getReturnType();
if (type == int.class) {
ret = ((Integer) m.invoke(a, null))
.compareTo((Integer) m.invoke(b, null));
} else if (type == double.class) {
ret = ((Double) m.invoke(a, null)).compareTo((Double) m
.invoke(b, null));
} else if (type == long.class) {
ret = ((Long) m.invoke(a, null)).compareTo((Long) m
.invoke(b, null));
} else if (type == float.class) {
ret = ((Float) m.invoke(a, null)).compareTo((Float) m
.invoke(b, null));
} else if (type == Date.class) {
ret = ((Date) m.invoke(a, null)).compareTo((Date) m
.invoke(b, null));
} else if (isImplementsOf(type, Comparable.class)) {
ret = ((Comparable) m.invoke(a, null))
.compareTo((Comparable) m.invoke(b, null));
} else {
ret = String.valueOf(m.invoke(a, null)).compareTo(
String.valueOf(m.invoke(b, null)));
}
if (isImplementsOf(type, Comparable.class)) {
ret = ((Comparable) m.invoke(a, null))
.compareTo((Comparable) m.invoke(b, null));
} else {
ret = String.valueOf(m.invoke(a, null)).compareTo(
String.valueOf(m.invoke(b, null)));
}
} catch (NoSuchMethodException ne) {
System.out.println(ne);
} catch (IllegalAccessException ie) {
System.out.println(ie);
} catch (InvocationTargetException it) {
System.out.println(it);
}
if (sort != null && sort.toLowerCase().equals(DESC)) {
return -ret;
} else {
return ret;
}
}
});
return list;
}
@SuppressWarnings("unchecked")
public static List<?> sortByMethod(List<?> list, final String methods[],
final String sorts[]) {
if (methods != null && methods.length > 0) {
for (int i = methods.length - 1; i >= 0; i--) {
final String method = methods[i];
String tmpSort = ASC;
if (sorts != null && sorts.length > i && sorts[i] != null) {
tmpSort = sorts[i];
}
final String sort = tmpSort;
Collections.sort(list, new Comparator() {
public int compare(Object a, Object b) {
int ret = 0;
try {
Method m = a.getClass().getMethod(method, null);
m.setAccessible(true);
Class<?> type = m.getReturnType();
if (type == int.class) {
ret = ((Integer) m.invoke(a, null))
.compareTo((Integer) m.invoke(b, null));
} else if (type == double.class) {
ret = ((Double) m.invoke(a, null))
.compareTo((Double) m.invoke(b, null));
} else if (type == long.class) {
ret = ((Long) m.invoke(a, null))
.compareTo((Long) m.invoke(b, null));
} else if (type == float.class) {
ret = ((Float) m.invoke(a, null))
.compareTo((Float) m.invoke(b, null));
} else if (type == Date.class) {
ret = ((Date) m.invoke(a, null))
.compareTo((Date) m.invoke(b, null));
} else if (isImplementsOf(type, Comparable.class)) {
ret = ((Comparable) m.invoke(a, null))
.compareTo((Comparable) m.invoke(b,
null));
} else {
ret = String.valueOf(m.invoke(a, null))
.compareTo(
String.valueOf(m
.invoke(b, null)));
}
} catch (NoSuchMethodException ne) {
System.out.println(ne);
} catch (IllegalAccessException ie) {
System.out.println(ie);
} catch (InvocationTargetException it) {
System.out.println(it);
}
if (sort != null && sort.toLowerCase().equals(DESC)) {
return -ret;
} else {
return ret;
}
}
});
}
}
return list;
}
/**
* 判断对象实现的所有接口中是否包含szInterface
*
* @param clazz
* @param szInterface
* @return
*/
public static boolean isImplementsOf(Class<?> clazz, Class<?> szInterface) {
boolean flag = false;
Class<?>[] face = clazz.getInterfaces();
for (Class<?> c : face) {
if (c == szInterface) {
flag = true;
} else {
flag = isImplementsOf(c, szInterface);
}
}
if (!flag && null != clazz.getSuperclass()) {
return isImplementsOf(clazz.getSuperclass(), szInterface);
}
return flag;
}
public static int atoi(String str) {
//这里要小心，需要判断有效性
if (str == null || str.length() == 0) {
return 0;
}
int nlen = str.length();
double sum = 0;
int sign = 1;
int j = 0;
//剔除空格
while (str.charAt(j) == ' ') {
j++;
}
//判断正数和负数
if (str.charAt(j) == '+') {
sign = 1;
j++;
} else if (str.charAt(j) == '-') {
sign = -1;
j++;
}
for (int i = j; i < nlen; i++) {
char current = str.charAt(i);
if (current >= '0' && current <= '9') {
sum = sum * 10 + (int) (current - '0');
} else {
break;//碰到非数字，退出转换
}
}
sum = sum * sign;
//这里要小心，需要判断范围
if (sum > Integer.MAX_VALUE) {
sum = Integer.MAX_VALUE;
} else if (sum < Integer.MIN_VALUE) {
sum = Integer.MIN_VALUE;
}
return (int) sum;
}
/**
* 按照自然语言顺序排序
*
* @param list
*/
public static void naturalSort(List<String> list) {
Collections.sort(list, (o1, o2) -> {
int i = 0, j = 0;
String temp1, temp2;
int num1, num2;
int length = Math.min(o1.length(), o2.length());
while (i < length && j < length) {
temp1 = "";
temp2 = "";
if (o1.charAt(i) > '9' || o1.charAt(i) < '0' || o2.charAt(j) > '9' || o2.charAt(j) < '0') {
if (o1.charAt(i) == o2.charAt(j)) {
i++;
j++;
continue;
} else if (o1.charAt(i) > o2.charAt(j)) {
return 1;
} else {
return -1;
}
}
while (i < o1.length() && o1.charAt(i) <= '9' && o1.charAt(i) >= '0') {
temp1 += o1.charAt(i);
i++;
}
while (j < o2.length() && o2.charAt(j) <= '9' && o2.charAt(j) >= '0') {
temp2 += o2.charAt(j);
j++;
}
num1 = atoi(temp1);
num2 = atoi(temp2);
if (num1 == num2) {
if (temp1.length() < temp2.length()) {
return 1;
} else if (temp1.length() > temp2.length()) {
return -1;
} else {
continue;
}
} else if (num1 > num2) {
return 1;
} else {
return -1;
}
}
return o1.length() > o2.length() ? 1 : -1;
});
}
}
标签：return,String,invoke,ret,else,SortListUtil,null 来源： https://www.cnblogs.com/wangpeng1201/p/16474344.html