一、前言
oracle和mysql的group by 分组功能大家应该清楚，那如何使用java实现同样的功能呢
比如下面这个表
id | name | age | math | English |
10 | yujianlin | 20 | 92.5 | |
103 | ww | 84 | ||
102 | 5 | 20 | ||
102 | 6 | 1 | ||
103 | 63 | |||
103 | 5 | |||
10 | 20 |
我们需要按id分组，求最大age和math累计成绩
我们的sql应该这样写
select id,max(age),sum(math)
from student
group by id;得到的数据是这样的
那java应该怎么样实现呢？
二、java实现过程
group by分组实现
public static Map<String, Object> groupBy(Map<String, Object> map, String[] groupFuns) {
// List list = new ArrayList(groupFuns.length);
if (groupFuns.length<1){
return map;
}
Map<String, Object> result = new HashMap<>();
for (int i = 0, length = groupFuns.length; i < length; i++) {
String field = groupFuns[i];
if (!map.containsKey(field)) {
System.out.println("map中未有【" + field + "】字段");
//log.error("map中未有【{}】字段",field);
continue;
}
Object value = map.get(field);
if (value == null || StringUtils.isBlank(value.toString())) {
result.put(field, null);
} else {
result.put(field, value);
}
}
return result;
}调用分组函数
public static List<Map<String, Object>> partitionGroupBy(List<Map<String, Object>> dataList, String[] groupFuns, String[][] combiFuns) {
Map<Map<String, Object>, List<Map<String, Object>>> groupByResultMap = dataList.stream().collect(Collectors.groupingBy(o -> groupBy(o, groupFuns)));
if (MapUtils.isEmpty(groupByResultMap)){
return new ArrayList<>();
}
List<Map<String, Object>> result = new ArrayList<>(groupByResultMap.size());
for (Map.Entry<Map<String, Object>, List<Map<String, Object>>> entry : groupByResultMap.entrySet()) {
Map<String, Object> key = entry.getKey();
List<Map<String, Object>> valueList = entry.getValue();
// {{"max","advancedate"},{"max","vc_code"},{"sum","cashdivirmb"}};
Map<String, Object> resultMap = new HashMap<>(16);
for (int i = 0, length = combiFuns.length; i < length; i++) {
String[] combiFun = combiFuns[i];
// 组合函数名称
String combiFunName = combiFun[0];
// 字段名称
String combiFunField = combiFun[1];
// 别名
String otherName = StringUtils.isBlank(combiFun[2]) ? combiFunField : combiFun[2];
switch (combiFunName.toLowerCase()) {
case "null":
resultMap.put(otherName, null);
break;
case "field":
// 原始字段值，从分组的key里面取值
resultMap.put(otherName, key.get(combiFunField));
break;
case "spel":
resultMap.putAll(combiFunSpel(resultMap, combiFunField, otherName,combiFun[3]));
break;
case "max":
resultMap.putAll(combiFunMax(valueList, combiFunField, otherName));
break;
case "min":
resultMap.putAll(combiFunMin(valueList, combiFunField, otherName));
break;
case "sum":
resultMap.putAll(combiFunSum(valueList, combiFunField,otherName));
break;
default:
System.out.println("不存在组合函数【" + combiFunName + "," + combiFunField + "】，请自己实现或者更改成已经有的组合函数");
//log.error("不存在组合函数【{},{}】，请自己实现或者更改成已经有的组合函数",combiFunName,combiFunField);
}
}
// List<Map<String, Object>> combiFunFilterList = new ArrayList<>();
// combiFunFilterList.add(resultMap);
result.add(resultMap);
}
return result;
}实现max，sum，min，spel表达式等自定义函数
private static Map<String, Object> combiFunMax(List<Map<String, Object>> list, String combiFunField, String otherName) {
BigDecimal maxValue = null;
for (Map<String, Object> map : list) {
if (!map.containsKey(combiFunField)) {
System.out.println("map中未有【" + combiFunField + "】字段");
//log.error("map中未有【{}】字段", combiFunField);
continue;
}
Object tempValueObj = map.get(combiFunField);
if (tempValueObj == null || StringUtils.isBlank(tempValueObj.toString())) {
continue;
}
BigDecimal tempValue = ComUtils.nvl(map.get(combiFunField), BigDecimal.ZERO);
if (maxValue == null || tempValue.compareTo(maxValue) > 0) {
maxValue = tempValue;
}
}
Map<String, Object> resultMap = new HashMap<>();
resultMap.put(otherName, maxValue);
return resultMap;
}
private static Map<String, Object> combiFunMin(List<Map<String, Object>> list, String combiFunField, String otherName) {
BigDecimal minValue = null;
for (Map<String, Object> map : list) {
if (!map.containsKey(combiFunField)) {
System.out.println("map中未有【" + combiFunField + "】字段");
//log.error("map中未有【{}】字段", combiFunField);
continue;
}
Object tempValueObj = map.get(combiFunField);
if (tempValueObj == null || StringUtils.isBlank(tempValueObj.toString())) {
continue;
}
BigDecimal tempValue = ComUtils.nvl(map.get(combiFunField), BigDecimal.ZERO);
if (minValue == null || tempValue.compareTo(minValue) < 0) {
minValue = tempValue;
}
}
Map<String, Object> resultMap = new HashMap<>();
resultMap.put(otherName, minValue);
return resultMap;
}
private static SpelCommonUtil spelCommonUtil=new SpelCommonUtil();
private static Map<String, Object> combiFunSpel(Map<String,Object> map, String combiFunField, String otherName,String spelFun) {
// spel
ExpressionParser parser = new SpelExpressionParser();
Expression exp = parser.parseExpression(spelFun);
StandardEvaluationContext context = new StandardEvaluationContext();
context.setRootObject(spelCommonUtil);
Map<String, Object> resultMap = new HashMap<>();
context.setVariable("a",map);
Object value = exp.getValue(context);
resultMap.put(otherName,value);
return resultMap;
}
private static Map<String, Object> combiFunSum(List<Map<String, Object>> list, String combiFunField,String otherName) {
BigDecimal sumValue = null;
for (Map<String, Object> map : list) {
if (!map.containsKey(combiFunField)) {
System.out.println("map中未有【" + combiFunField + "】字段");
//log.error("map中未有【{}】字段", combiFunField);
continue;
}
Object tempValueObj = map.get(combiFunField);
if (tempValueObj == null || StringUtils.isBlank(tempValueObj.toString())) {
continue;
}
BigDecimal tempValue = ComUtils.nvl(map.get(combiFunField), BigDecimal.ZERO);
sumValue = tempValue.add(sumValue == null ? BigDecimal.ZERO : sumValue);
}
Map<String, Object> resultMap = new HashMap<>();
resultMap.put(otherName, sumValue);
return resultMap;
}测试类调用
public static void main(String[] args) {
Map<String, Object> map1 = new HashMap<String, Object>() {{
put("id", 10);
put("name", "map1");
put("age", "20");
put("math", "92.5");
}};
Map<String, Object> map2 = new HashMap<String, Object>() {{
put("id", 103);
put("name", "map2");
put("age", "");
put("math", "84");
}};
Map<String, Object> map3 = new HashMap<String, Object>() {{
put("id", 102);
put("name", "map3");
put("age", "5");
put("math", "20");
}};
Map<String, Object> map4 = new HashMap<String, Object>() {{
put("id", 102);
put("name", "map4");
put("age", "6");
put("math", "1");
}};
Map<String, Object> map5 = new HashMap<String, Object>() {{
put("id", 103);
put("name", "map5");
put("age", null);
put("math", "63");
}};
Map<String, Object> map6 = new HashMap<String, Object>() {{
put("id", 103);
put("name", "map6");
put("age", 5);
put("math", "");
}};
Map<String, Object> map7 = new HashMap<String, Object>() {{
put("id", 10);
put("name", "map7");
put("age", "20");
put("math", "");
}};
List<Map<String, Object>> list = new ArrayList<Map<String, Object>>() {{
add(map1);
add(map2);
add(map3);
add(map4);
add(map5);
add(map6);
add(map7);
}};
String[] groupFuns = {"id"};
//String[] groupFuns = {"id","age"};
// 组合函数，取的字段，别名(如果为空就以取的字段为key)，特殊处理函数
//String[][] combiFuns = {{"min", "age", "", ""}, {"field", "id", "", ""}, {"sum", "math", "", ""},{"spel", "age", "spel", "decode(#a.get(\"age\"),5,\"优秀\",\"不优秀\")"}};
// String[][] combiFuns = {{"min", "age", "", ""}, {"field", "id", "", ""}, {"sum", "math", "", ""}};
String[][] combiFuns = {{"max", "age", "", ""},{"max", "math", "", ""}};
List<Map<String, Object>> maps = partitionGroupBy(list, groupFuns, combiFuns);
System.out.println(maps);
System.out.println(JSON.toJSONString(maps));
}执行测试结果
发现和数据库执行的一致，符合要求
复杂情况casewhen函数
那要是还是按id，age分组，sum(math)>60为及格，否则为不及格应该怎么写呢？
sql语句应该为
select id,max(age),sum(math),case when sum(math)>60 then '及格' else '不及格' end as pingjia
from student
group by id,age;执行结果
java应该怎么实现呢，这里就需要用到spel表达式，不了解的朋友们可以去找一下资料，这里就不赘述了
这里就得加spel常用的一些表达式，具体请看文末的，spelCommonUtil.class
java测试
分组和函数配置如下
String[] groupFuns = {"id","age"};
String[][] combiFuns = {{"field", "id", "", ""},{"max", "age", "", ""},{"sum", "math", "", ""},{"spel","math","pingjia","caseWhen(\"不及格\",#a.get(\"math\")>60,\"及格\")"}};public static void main(String[] args) {
Map<String, Object> map1 = new HashMap<String, Object>() {{
put("id", 10);
put("name", "map1");
put("age", "20");
put("math", "92.5");
}};
Map<String, Object> map2 = new HashMap<String, Object>() {{
put("id", 103);
put("name", "map2");
put("age", "");
put("math", "84");
}};
Map<String, Object> map3 = new HashMap<String, Object>() {{
put("id", 102);
put("name", "map3");
put("age", "5");
put("math", "20");
}};
Map<String, Object> map4 = new HashMap<String, Object>() {{
put("id", 102);
put("name", "map4");
put("age", "6");
put("math", "1");
}};
Map<String, Object> map5 = new HashMap<String, Object>() {{
put("id", 103);
put("name", "map5");
put("age", null);
put("math", "63");
}};
Map<String, Object> map6 = new HashMap<String, Object>() {{
put("id", 103);
put("name", "map6");
put("age", 5);
put("math", "");
}};
Map<String, Object> map7 = new HashMap<String, Object>() {{
put("id", 10);
put("name", "map7");
put("age", "20");
put("math", "");
}};
List<Map<String, Object>> list = new ArrayList<Map<String, Object>>() {{
add(map1);
add(map2);
add(map3);
add(map4);
add(map5);
add(map6);
add(map7);
}};
//String[] groupFuns = {"id"};
String[] groupFuns = {"id","age"};
// 组合函数，取的字段，别名(如果为空就以取的字段为key)，特殊处理函数
//String[][] combiFuns = {{"min", "age", "", ""}, {"field", "id", "", ""}, {"sum", "math", "", ""},{"spel", "age", "spel", "decode(#a.get(\"age\"),5,\"优秀\",\"不优秀\")"}};
// String[][] combiFuns = {{"min", "age", "", ""}, {"field", "id", "", ""}, {"sum", "math", "", ""}};
//String[][] combiFuns = {{"field", "id", "", ""},{"max", "age", "", ""},{"max", "math", "", ""}};
//String[][] combiFuns = {{"field", "id", "", ""},{"max", "age", "", ""},{"sum", "math", "", ""}};
String[][] combiFuns = {{"field", "id", "", ""},{"max", "age", "", ""},{"sum", "math", "", ""},{"spel","math","pingjia","caseWhen(\"不及格\",#a.get(\"math\")>60,\"及格\")"}};
List<Map<String, Object>> maps = partitionGroupBy(list, groupFuns, combiFuns);
System.out.println(maps);
System.out.println(JSON.toJSONString(maps));
}执行结果
结果和sql执行一致，符合要求，
优化代码
综上所述，代码符合要求，但是有一种情况该方法就无法实现，比如我们需要求按id和age分组，同时满足max(age)>5 和 sum(math)>60 的，上述代码就无法实现，因为这里出现了分组函数和case when函数同时出现的情况
我们将在另外的代码中优化，具体请看下期
三、完整代码
import com.alibaba.fastjson.JSON;
import org.apache.commons.collections.MapUtils;
import org.apache.commons.lang3.StringUtils;
import org.springframework.expression.Expression;
import org.springframework.expression.ExpressionParser;
import org.springframework.expression.spel.standard.SpelExpressionParser;
import org.springframework.expression.spel.support.StandardEvaluationContext;
import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;
public class Test14 {
public static void main(String[] args) {
Map<String, Object> map1 = new HashMap<String, Object>() {{
put("id", 10);
put("name", "map1");
put("age", "20");
put("math", "92.5");
}};
Map<String, Object> map2 = new HashMap<String, Object>() {{
put("id", 103);
put("name", "map2");
put("age", "");
put("math", "84");
}};
Map<String, Object> map3 = new HashMap<String, Object>() {{
put("id", 102);
put("name", "map3");
put("age", "5");
put("math", "20");
}};
Map<String, Object> map4 = new HashMap<String, Object>() {{
put("id", 102);
put("name", "map4");
put("age", "6");
put("math", "1");
}};
Map<String, Object> map5 = new HashMap<String, Object>() {{
put("id", 103);
put("name", "map5");
put("age", null);
put("math", "63");
}};
Map<String, Object> map6 = new HashMap<String, Object>() {{
put("id", 103);
put("name", "map6");
put("age", 5);
put("math", "");
}};
Map<String, Object> map7 = new HashMap<String, Object>() {{
put("id", 10);
put("name", "map7");
put("age", "20");
put("math", "");
}};
List<Map<String, Object>> list = new ArrayList<Map<String, Object>>() {{
add(map1);
add(map2);
add(map3);
add(map4);
add(map5);
add(map6);
add(map7);
}};
//String[] groupFuns = {"id"};
String[] groupFuns = {"id","age"};
// 组合函数，取的字段，别名(如果为空就以取的字段为key)，特殊处理函数
//String[][] combiFuns = {{"min", "age", "", ""}, {"field", "id", "", ""}, {"sum", "math", "", ""},{"spel", "age", "spel", "decode(#a.get(\"age\"),5,\"优秀\",\"不优秀\")"}};
// String[][] combiFuns = {{"min", "age", "", ""}, {"field", "id", "", ""}, {"sum", "math", "", ""}};
//String[][] combiFuns = {{"field", "id", "", ""},{"max", "age", "", ""},{"max", "math", "", ""}};
//String[][] combiFuns = {{"field", "id", "", ""},{"max", "age", "", ""},{"sum", "math", "", ""}};
String[][] combiFuns = {{"field", "id", "", ""},{"max", "age", "", ""},{"sum", "math", "", ""},{"spel","math","pingjia","caseWhen(\"不及格\",#a.get(\"math\")>60,\"及格\")"}};
List<Map<String, Object>> maps = partitionGroupBy(list, groupFuns, combiFuns);
System.out.println(maps);
System.out.println(JSON.toJSONString(maps));
}
public static List<Map<String, Object>> partitionGroupBy(List<Map<String, Object>> dataList, String[] groupFuns, String[][] combiFuns) {
Map<Map<String, Object>, List<Map<String, Object>>> groupByResultMap = dataList.stream().collect(Collectors.groupingBy(o -> groupBy(o, groupFuns)));
if (MapUtils.isEmpty(groupByResultMap)){
return new ArrayList<>();
}
List<Map<String, Object>> result = new ArrayList<>(groupByResultMap.size());
for (Map.Entry<Map<String, Object>, List<Map<String, Object>>> entry : groupByResultMap.entrySet()) {
Map<String, Object> key = entry.getKey();
List<Map<String, Object>> valueList = entry.getValue();
// {{"max","advancedate"},{"max","vc_code"},{"sum","cashdivirmb"}};
Map<String, Object> resultMap = new HashMap<>(16);
for (int i = 0, length = combiFuns.length; i < length; i++) {
String[] combiFun = combiFuns[i];
// 组合函数名称
String combiFunName = combiFun[0];
// 字段名称
String combiFunField = combiFun[1];
// 别名
String otherName = StringUtils.isBlank(combiFun[2]) ? combiFunField : combiFun[2];
switch (combiFunName.toLowerCase()) {
case "null":
resultMap.put(otherName, null);
break;
case "field":
// 原始字段值，从分组的key里面取值
resultMap.put(otherName, key.get(combiFunField));
break;
case "spel":
resultMap.putAll(combiFunSpel(resultMap, combiFunField, otherName,combiFun[3]));
break;
case "max":
resultMap.putAll(combiFunMax(valueList, combiFunField, otherName));
break;
case "min":
resultMap.putAll(combiFunMin(valueList, combiFunField, otherName));
break;
case "sum":
resultMap.putAll(combiFunSum(valueList, combiFunField,otherName));
break;
default:
System.out.println("不存在组合函数【" + combiFunName + "," + combiFunField + "】，请自己实现或者更改成已经有的组合函数");
//log.error("不存在组合函数【{},{}】，请自己实现或者更改成已经有的组合函数",combiFunName,combiFunField);
}
}
// List<Map<String, Object>> combiFunFilterList = new ArrayList<>();
// combiFunFilterList.add(resultMap);
result.add(resultMap);
}
return result;
}
public static Map<String, Object> groupBy(Map<String, Object> map, String[] groupFuns) {
// List list = new ArrayList(groupFuns.length);
if (groupFuns.length<1){
return map;
}
Map<String, Object> result = new HashMap<>();
for (int i = 0, length = groupFuns.length; i < length; i++) {
String field = groupFuns[i];
if (!map.containsKey(field)) {
System.out.println("map中未有【" + field + "】字段");
//log.error("map中未有【{}】字段",field);
continue;
}
Object value = map.get(field);
if (value == null || StringUtils.isBlank(value.toString())) {
result.put(field, null);
} else {
result.put(field, value);
}
}
return result;
}
private static Map<String, Object> combiFunMax(List<Map<String, Object>> list, String combiFunField, String otherName) {
BigDecimal maxValue = null;
for (Map<String, Object> map : list) {
if (!map.containsKey(combiFunField)) {
System.out.println("map中未有【" + combiFunField + "】字段");
//log.error("map中未有【{}】字段", combiFunField);
continue;
}
Object tempValueObj = map.get(combiFunField);
if (tempValueObj == null || StringUtils.isBlank(tempValueObj.toString())) {
continue;
}
BigDecimal tempValue = ComUtils.nvl(map.get(combiFunField), BigDecimal.ZERO);
if (maxValue == null || tempValue.compareTo(maxValue) > 0) {
maxValue = tempValue;
}
}
Map<String, Object> resultMap = new HashMap<>();
resultMap.put(otherName, maxValue);
return resultMap;
}
private static Map<String, Object> combiFunMin(List<Map<String, Object>> list, String combiFunField, String otherName) {
BigDecimal minValue = null;
for (Map<String, Object> map : list) {
if (!map.containsKey(combiFunField)) {
System.out.println("map中未有【" + combiFunField + "】字段");
//log.error("map中未有【{}】字段", combiFunField);
continue;
}
Object tempValueObj = map.get(combiFunField);
if (tempValueObj == null || StringUtils.isBlank(tempValueObj.toString())) {
continue;
}
BigDecimal tempValue = ComUtils.nvl(map.get(combiFunField), BigDecimal.ZERO);
if (minValue == null || tempValue.compareTo(minValue) < 0) {
minValue = tempValue;
}
}
Map<String, Object> resultMap = new HashMap<>();
resultMap.put(otherName, minValue);
return resultMap;
}
private static SpelCommonUtil spelCommonUtil=new SpelCommonUtil();
private static Map<String, Object> combiFunSpel(Map<String,Object> map, String combiFunField, String otherName,String spelFun) {
// spel
ExpressionParser parser = new SpelExpressionParser();
Expression exp = parser.parseExpression(spelFun);
StandardEvaluationContext context = new StandardEvaluationContext();
context.setRootObject(spelCommonUtil);
Map<String, Object> resultMap = new HashMap<>();
context.setVariable("a",map);
Object value = exp.getValue(context);
resultMap.put(otherName,value);
return resultMap;
}
private static Map<String, Object> combiFunSum(List<Map<String, Object>> list, String combiFunField,String otherName) {
BigDecimal sumValue = null;
for (Map<String, Object> map : list) {
if (!map.containsKey(combiFunField)) {
System.out.println("map中未有【" + combiFunField + "】字段");
//log.error("map中未有【{}】字段", combiFunField);
continue;
}
Object tempValueObj = map.get(combiFunField);
if (tempValueObj == null || StringUtils.isBlank(tempValueObj.toString())) {
continue;
}
BigDecimal tempValue = ComUtils.nvl(map.get(combiFunField), BigDecimal.ZERO);
sumValue = tempValue.add(sumValue == null ? BigDecimal.ZERO : sumValue);
}
Map<String, Object> resultMap = new HashMap<>();
resultMap.put(otherName, sumValue);
return resultMap;
}
}
ComUtils.class
import org.apache.commons.collections.CollectionUtils;
import org.apache.commons.collections.MapUtils;
import org.apache.commons.lang3.StringUtils;
import org.springframework.expression.Expression;
import org.springframework.expression.ExpressionParser;
import org.springframework.expression.spel.standard.SpelExpressionParser;
import org.springframework.expression.spel.support.StandardEvaluationContext;
import java.math.BigDecimal;
import java.text.SimpleDateFormat;
import java.util.*;
import java.util.stream.Collectors;
public class ComUtils {
/**
* SpelCommonUtil
*/
private static SpelCommonUtil spelCommonUtil = new SpelCommonUtil();
/**
* nvl转换函数
*
* @param obj1
* @param obj2
* @return
*/
public static BigDecimal nvl(Object obj1, BigDecimal obj2) {
if (obj1 == null) {
return obj2;
}
if (StringUtils.isBlank(obj1.toString())) {
return obj2;
}
return new BigDecimal(obj1.toString());
}
/**
* nvl转换函数
*
* @param obj1
* @param obj2
* @return
*/
public static String nvl(Object obj1, String obj2) {
if (obj1 == null) {
return obj2;
}
if (StringUtils.isBlank(obj1.toString())) {
return obj2;
}
return obj1.toString();
}
}
SpelCommonUtil.class
package com.zygxsq.test.util;
import org.apache.commons.lang3.ObjectUtils;
import org.apache.commons.lang3.StringUtils;
import java.math.BigDecimal;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Date;
import java.util.List;
import java.util.UUID;
public class SpelCommonUtil {
private static ThreadLocal<DateFormat> threadLocal = new ThreadLocal<DateFormat>() {
protected DateFormat initialValue() {
return new SimpleDateFormat("yyyyMMdd");
}
};
/**
* 日期格式转换为Integer
* @date 2022-10-21 17:06
* @param date
* @return java.lang.Integer
**/
public static Integer dateToInt(Date date){
if (null==date){
return null;
}
return Integer.valueOf( threadLocal.get().format(date));
}
/**
* 相除
* 修正原因：保留精度 默认保留小数位 10位
* 入参格式：division(#a.get('xxx'),100,4)-》表示除以100 保留4位
* 注意点：
* 精度具体值 来源于具体表的具体字段的数据定义
* @param numerator
* @param denominator
* @return
*/
public static BigDecimal division(Object numerator , Object... values){
if (null ==numerator){
return null;
}
if (null==values || values.length<=0){
return null;
}
Object denominator = values[0];
if (denominator == null){
return null;
}
BigDecimal numeratorDouble=new BigDecimal(numerator.toString());
BigDecimal denominatorDouble=new BigDecimal(denominator.toString());
if (denominatorDouble.doubleValue()==0){
return null;
}
// 默认保留 10位
int scale = 10;
// 传入精度时 替换
if (values.length>1){
scale = values[1] != null? Integer.valueOf(values[1].toString()) :scale;
}
return numeratorDouble.divide(denominatorDouble,scale,BigDecimal.ROUND_HALF_UP);
}
/**
* 相乘
* 修改原因：精度的问题
* @param numerator
* @param denominator
* @return
*/
public static BigDecimal multiply(Object numerator , Object denominator){
if (null ==numerator||null==denominator){
return null;
}
BigDecimal numeratorBigDecimal=new BigDecimal(numerator.toString());
BigDecimal denominatorBigDecimal=new BigDecimal(denominator.toString());
return numeratorBigDecimal.multiply(denominatorBigDecimal);
}
/**
* 相减
* @param num1 被减数
* @param num2 减数
* @return
*/
public static BigDecimal subtract(Object num1, Object num2){
if (null == num1 || null == num2){
return null;
}
BigDecimal bigDecimal1 = new BigDecimal(num1.toString());
BigDecimal bigDecimal2 = new BigDecimal(num2.toString());
return bigDecimal1.subtract(bigDecimal2);
}
/**
* 获取当前日期
*
* @date 2022-10-21 17:10
* @return java.util.Date
**/
public static Date now(){
return new Date();
}
/**
* 三目运算
* @param obj1
* @param obj2
* @return
*/
public static Object nvl(Object obj1 , Object obj2){
return null == obj1?obj2:obj1;
}
/**
* 三目运算
* @param obj1
* @param obj2
* @return
*/
public static Object nvl2(Object obj1 , Object obj2, Object obj3){
return null == obj1?obj3:obj2;
}
/**
* 字符串截取，对应Oracle substr 例如：substr(#t.get("dm"), 1, 4)
* @param obj
* @param index
* @return
*/
public static String substr(Object obj, Integer... index) {
StringBuilder result = new StringBuilder();
if (null == obj) {
return result.toString();
}
String str = obj.toString();
// 针对 从后面截取
if (index.length == 1) {
// 如截取 -2
if (index[0] < 0 && Math.abs(index[0]) <= str.length()) {
return str.substring(str.length()+ index[0]);
}
// 超过 返回空字符串
if (index[0] < 0 && Math.abs(index[0]) > str.length()) {
return "";
}
}
if (index.length==2){
if (index[0] == 0 || index[0] == 1){
if (index[0]+index[1]-1>str.length()){
result.append(str.substring(0,str.length()));
}else{
result.append(str.substring(0,index[0]+index[1]-1));
}
}else{
if (index[0]+index[1]-1>str.length()){
result.append(str.substring(index[0]-1,str.length()));
}else{
result.append(str.substring(index[0]-1,index[0]+index[1]-1));
}
}
}else if (index.length==1){
if (index[0] == 0 || index[0] == 1){
result.append(str.substring(0));
}else{
result.append(str.substring(index[0]-1));
}
}else{
result.append(str);
}
return result.toString();
}
/**
* 字符串拼接 对应Oracle || 例如：append("2",#a.get("id"))
* @param strs
* @return
*/
public static String append(Object... strs){
StringBuilder result = new StringBuilder();
for (int i=0;i<strs.length;i++){
if (null != strs[i]){
result.append(strs[i]);
}
}
return result.toString();
}
/**
* 条件判断 例：caseWhen(默认值,条件1,值1,条件2,值2) 例如：caseWhen(0,in(#a.get("companynature"),"(172,420)"),1)
* @param defaultValue 默认值
* @param conditions 条件
* @return
*/
public static Object caseWhen(Object defaultValue, Object... conditions){
Object result = defaultValue;
for (int i=0;i<conditions.length;){
if ("true".equals(conditions[i].toString())){
result = conditions[i+1];
break;
}
i=i+2;
}
return result;
}
/**
* oracle 的decode函数，不支持value为null，有为null请使用caseWhen()
* 例：decode(#a.get("companynature"),1,1,19,2,20,3,null)
* @param value
* @param conditions
* @return
*/
public static Object decode(Object value, Object... conditions) {
if (conditions == null) {
throw new BatchException("decode值不能为空");
}
int three = 3;
int one = 1;
if (conditions.length < three || (conditions.length & one) == 0) {
throw new BatchException("decode值不符合要求");
}
Object result = conditions[conditions.length - 1];
if (value == null) {
return result;
}
for (int i = 0; i < conditions.length; ) {
if (conditions[i] == null) {
throw new BatchException("decode中的比较值不能为null");
}
if (value != null && conditions[i] != null) {
if (StringUtils.equals(value.toString(), conditions[i].toString())) {
result = conditions[i + 1];
break;
}
} else if (value == null && conditions[i] == null) {
result = conditions[i + 1];
break;
}
i = i + 2;
}
return result;
}
/**
*
* @param obj in(#a.get("companynature"),"172,420"))
* @param condition
* @return
*/
public static boolean in(Object obj, String condition){
if (StringUtils.isBlank(condition) || obj == null){
return false;
}
String[] values = condition.split(",");
List<String> valueList = new ArrayList(Arrays.asList(values));
return valueList.contains(obj);
}
/** 对应数值类型
* @param obj in(#a.get("l_market"),1,2))
* @param condition
* @return
*/
public static boolean in(Object obj, Integer... condition) {
if (condition.length == 0 || obj == null) {
return false;
}
if (obj instanceof BigDecimal || obj instanceof Double) {
obj = ((Number) obj).intValue();
}
List<Integer> valueList = new ArrayList(Arrays.asList(condition));
return valueList.contains(obj);
}
/**
* 不在 -> true
* @param obj inNot(#a.get("companynature"),"172,420"))
* @param condition
* @return
*/
public static boolean inNot(Object obj, String condition){
if (StringUtils.isBlank(condition) || obj == null){
return false;
}
String[] values = condition.split(",");
List<String> valueList = new ArrayList(Arrays.asList(values));
return !valueList.contains(obj);
}
/**
* 对应数据库左like，例如：%11
* @param obj
* @param condition
* @return
*/
public static boolean likeOnLeft(Object obj,String condition){
if (null == obj){
return false;
}
return obj.toString().endsWith(condition);
}
/**
* 对应数据库右like，例如：11% likeOnRight(#a.get("chiname"),"中华人民共和国")
* @param obj
* @param condition
* @return
*/
public static boolean likeOnRight(Object obj,String condition){
if (null == obj){
return false;
}
return obj.toString().startsWith(condition);
}
/**
* 对应数据库like，例如：11%22
* @param obj
* @param condition
* @return
*/
public static boolean likeOnCenter(Object obj,String condition){
if (null == obj){
return false;
}
return obj.toString().contains(condition);
}
/**
* 对应数据库to_char,当需要转换的类型为日期格式，可以传第二个参数，例如"yyyyMMdd"，默认"yyyyMMdd"
* @param obj
* @return
*/
public static String toString(Object... obj){
String defaultFormat = "yyyyMMdd";
if (obj.length == 1){
if (null == obj[0]){
return null;
}else{
return obj[0].toString();
}
}else if (obj.length == 2){
if (null == obj[0]) {
return null;
}
if (obj[0] instanceof Date){
if (ObjectUtils.isNotEmpty(obj[1])){
SimpleDateFormat sdf;
// 容错 避免因为大小写的问题
if (defaultFormat.equalsIgnoreCase(obj[1].toString())) {
sdf = new SimpleDateFormat(defaultFormat);
}
else {
sdf = new SimpleDateFormat(obj[1].toString());
}
return sdf.format(obj[0]);
} else {
SimpleDateFormat sdf = new SimpleDateFormat(defaultFormat);
return sdf.format(obj[0]);
}
}else{
return obj[0].toString();
}
}else{
return null;
}
}
/**
* 对应数据库to_char,当需要转换的类型为日期格式，可以传第二个参数，例如"yyyyMMdd"，默认"yyyyMMdd"
* @param obj
* @return
*/
public static String toChar(Object... obj){
return toString(obj);
}
/**
* 对应数据库to_number
* @param obj
* @return
*/
public static Integer toNumber(Object obj){
if (ObjectUtils.isEmpty(obj)){
return null;
}
if (obj instanceof String){
return Integer.valueOf(obj.toString());
}
return null;
}
/**
* 系统参数校验
*
* @date 2022-12-01 15:26
* @param paramKey
* @param paramValue
* @return boolean
**/
public static boolean readtsysparameter(Integer paramKey,String paramValue){
String param= LoadDataConfigCache.getTetlparameterByKey(paramKey);
if (StringUtils.isBlank(param)){
return false;
}
if (param.equals(paramValue)){
return true;
}
return false;
}
/**
* 对应Oracle instr 判断str1中是否包含str2
* @param str1
* @param str2
* @return
*/
public static boolean contains(String str1, String str2){
if (StringUtils.isEmpty(str1)){
return false;
}
return str1.contains(str2);
}
/**
* 去空格 例如：trim(#a.get("businessmajor"))
* @param str
* @return
*/
public static String trim(Object str){
String result = "";
if (null == str){
return result;
}
if (str instanceof String){
result = str.toString().trim();
}
return result;
}
/**
* 对应Oracle replace
* @param str
* @param str1
* @param str2
* @return
*/
public static String replace(String str, String str1, String str2){
return str.replace(str1,str2);
}
/**
* 对应Oracle upper
* @param str
* @return
*/
public static String upper(String str){
return str.toUpperCase();
}
/**
* 对应Oracle lower
* @param str
* @return
*/
public static String lower(String str){
return str.toLowerCase();
}
/**
* 对应Oracle =
* @param obj1
* @param obj2
* @return
*/
public static boolean equal(Object obj1, Object obj2){
if (null == obj1){
return false;
}
return obj1.equals(obj2);
}
/** 不相等
* 对应Oracle != 和 <>
* @param obj1
* @param obj2
* @return
*/
public static boolean equalNot(Object obj1, Object obj2){
if (null == obj1){
return false;
}
return !obj1.equals(obj2);
}
/**
* 对应Oracle round
* @param number
* @param decimals
* @return
*/
public static BigDecimal round(Object number, int decimals){
BigDecimal result = new BigDecimal(0);
if (number instanceof Double){
result = new BigDecimal((double) number);
}
else if (number instanceof Integer){
result = new BigDecimal((int) number);
}
else if (number instanceof String){
result = new BigDecimal((String) number);
} else if (number instanceof BigDecimal){
result=(BigDecimal) number;
}
return result.setScale(decimals, BigDecimal.ROUND_HALF_UP);
}
/**
* oracle中sys_guid()
* @return
*/
public static String guid(){
return UUID.randomUUID().toString().replaceAll("-","");
}
}
