简单drools规则java代码自动生成

简单drools规则自动生成

  规则自动生成，drools也提供了支持，比如：

1.决策表（decision table）https://docs.jboss.org/drools/release/6.5.0.Final/drools-docs/html_single/index.html#d0e5713，

2.规则模板（Rule Templates）https://docs.jboss.org/drools/release/6.5.0.Final/drools-docs/html_single/index.html#d0e6464

3. 流式API http://docs.jboss.org/drools/release/5.2.0.Final/droolsjbpm-introduction-docs/html/ch02.html#d0e124

  不过由于现实环境中，我们会根据Excel 文件提供规则描述，解析动态生成规则，如果产品给的是决策表，那就很容易了，不过产品一般会根据自己的喜好，制定自己的"决策表".

  比如：（一行放不下，截取了两种图）

      博文http://blog.csdn.net/doctor_who2004/article/details/72600232介绍了如何读取Excel文件转换为java类，此不复述。

    文件中的内容对应的java类：

package com.beaver.drools.exampl.travel.rule;

import org.javafunk.excelparser.annotations.ExcelField;
import org.javafunk.excelparser.annotations.ExcelObject;
import org.javafunk.excelparser.annotations.ParseType;

/**
 * Created by beaver on 2017/5/20.
 */
@ExcelObject(parseType = ParseType.ROW, start = 2, end = 61)
public class TravelRule {
    
    //公司名称
    @ExcelField(position = 1)
    private String companyName;
    
    //费用类型
    @ExcelField(position = 2)
    private String expenseType;
    
    //规则应用场景
    @ExcelField(position = 3)
    private String applyPoint;
    
    //规则结果
    @ExcelField(position = 4)
    private String ruleAction;
    
    //规则内容
    @ExcelField(position = 7)
    private String rule;
    
    //提示信息
    @ExcelField(position = 9)
    private String alertMessage;
    
    //规则ID
    @ExcelField(position = 11)
    private String ruleId;
    
    //解析出的drools规则内容
    private String droolsRule;
    
    public String getCompanyName() {
        return companyName;
    }
    
    public void setCompanyName(String companyName) {
        this.companyName = companyName;
    }
    
    public String getExpenseType() {
        return expenseType;
    }
    
    public void setExpenseType(String expenseType) {
        this.expenseType = expenseType;
    }
    
    public String getRule() {
        return rule;
    }
    
    public void setRule(String rule) {
        this.rule = rule;
    }
    
    public String getApplyPoint() {
        return applyPoint;
    }
    
    public void setApplyPoint(String applyPoint) {
        this.applyPoint = applyPoint;
    }
    
    public String getRuleAction() {
        return ruleAction;
    }
    
    public void setRuleAction(String ruleAction) {
        this.ruleAction = ruleAction;
    }
    
    public String getAlertMessage() {
        return alertMessage;
    }
    
    public void setAlertMessage(String alertMessage) {
        this.alertMessage = alertMessage;
    }
    
    public String getRuleId() {
        return ruleId;
    }
    
    public void setRuleId(String ruleId) {
        this.ruleId = ruleId;
    }
    
    public String getDroolsRule() {
        return droolsRule;
    }
    
    public void setDroolsRule(String droolsRule) {
        this.droolsRule = droolsRule;
    }
    
    @Override
    public String toString() {
        return "TravelRule{" +
                "companyName='" + companyName + '\'' +
                ", expenseType='" + expenseType + '\'' +
                ", applyPoint='" + applyPoint + '\'' +
                ", ruleAction='" + ruleAction + '\'' +
                ", rule='" + rule + '\'' +
                ", alertMessage='" + alertMessage + '\'' +
                ", ruleId='" + ruleId + '\'' +
                ", droolsRule='" + droolsRule + '\'' +
                '}';
    }
}

   规则内when条件的匹配对象一般我们使用java中自定义的类最好，此类为：

package com.beaver.drools.exampl.travel.rule;

import com.beaver.drools.common.model.RuleResult;
import lombok.Data;

import java.util.HashMap;
import java.util.Map;

/**
 * Created by beaver on 2017/5/20.
 */
@Data
public class MatchInvoiceTravelRuleRequestDto {
    //规则ID
    private String ruleOID;
    
    //出差申请ID
    private String invoiceOID;
    
    //出差信息-人员级别、出差地点、出差费用等等
    private Map data = new HashMap<>();
    
    //规则执行结果
    private RuleResult result = RuleResult.OK;
    
    //备注-规则明细
    private String remarkMessage;
    
}

   本博文只是实现简单drools规则的自动生成，一个简单的规则的定义如下：

package com.beaver.drools.exampl.travel.rule;

import com.beaver.drools.common.model.RuleResult;
import com.google.common.base.Splitter;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.tuple.Pair;

import java.util.*;
import java.util.Map.Entry;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.stream.Collectors;

/**
 * Created by beaver on 2017/5/20.

 * 简单规则组成,并不不包含drools复杂的语法规则
 */
public class TravelRuleGenerate {
    //规则包名
    private String packageName;
    //规则需要外部类的包
    private List importPackages = new ArrayList<>();
    //规则名字
    private String ruleName;
    
    //规则匹配的类型，如 $o: OrderItem( $p : price, $code : custCode )中的OrderItem
    private String objectType;
    
    //规则匹配类型的变量名，如 $o: OrderItem( $p : price, $code : custCode )中的OrderItem中$o
    private String objectVar;
    
    //规则信息
    private TravelRule travelRule;
    
    //规则执行动作结果赋值属性名，如 $invoice.setResult(RuleResult.REJECT); 中的resultr;
    private String resultPropertyName;
    //规则执行动作结果的提示信息赋值属性名，如   $invoice.setRemarkMessage("您的房费高于公司标准 ");中的remarkMessage.
    private String alertMessagePropertyName;
    
    //规则匹配属性别名，如data["EXPENSE_LEVEL"] not in ("总裁"),
    // 中的EXPENSE_LEVEL在travelRule中droolsRule中的名不一样，类似mybatis映射一下
    //不过key为正则表达式
    private Map rulePropertyNameAlias = new HashMap<>();
    
    public String getPackageName() {
        return packageName;
    }
    
    public void setPackageName(String packageName) {
        this.packageName = packageName;
    }
    
    public List getImportPackages() {
        return importPackages;
    }
    
    public void setImportPackages(List importPackages) {
        this.importPackages = importPackages;
    }
    
    public String getRuleName() {
        return ruleName;
    }
    
    public void setRuleName(String ruleName) {
        this.ruleName = ruleName;
    }
    
    public TravelRule getTravelRule() {
        return travelRule;
    }
    
    public void setTravelRule(TravelRule travelRule) {
        this.travelRule = travelRule;
    }
    
    public String getObjectType() {
        return objectType;
    }
    
    public void setObjectType(String objectType) {
        this.objectType = objectType;
    }
    
    public String getObjectVar() {
        return objectVar;
    }
    
    public void setObjectVar(String objectVar) {
        this.objectVar = objectVar;
    }
    
    public String getResultPropertyName() {
        return resultPropertyName;
    }
    
    public void setResultPropertyName(String resultPropertyName) {
        this.resultPropertyName = resultPropertyName;
    }
    
    public String getAlertMessagePropertyName() {
        return alertMessagePropertyName;
    }
    
    public void setAlertMessagePropertyName(String alertMessagePropertyName) {
        this.alertMessagePropertyName = alertMessagePropertyName;
    }
    
    public Map getRulePropertyNameAlias() {
        return rulePropertyNameAlias;
    }
    
    public void setRulePropertyNameAlias(Map rulePropertyNameAlias) {
        this.rulePropertyNameAlias = rulePropertyNameAlias;
    }
    }

其中 ，

//规则信息
private TravelRule travelRule;

是我们解析Excel文件得到的原生规则，我们需要对其处理，生成drools规则描述。

下面的定义主要是为业务和代码需求定制，Excel文件中规则属性名多个对应一个意思，后者和我们java代码定义的不一样，所以类似mybatis，做个映射。

//规则匹配属性别名，如data["EXPENSE_LEVEL"] not in ("总裁"),
// 中的EXPENSE_LEVEL在travelRule中droolsRule中的名不一样，类似mybatis映射一下
//不过key为正则表达式
private Map rulePropertyNameAlias = new HashMap<>();

下面代码是对

private TravelRule travelRule;

及本类提供的规则信息产生drools规则，实现是比较笨重的方法，因为规则比较简单，复杂的规则如何实现呢？

package com.beaver.drools.exampl.travel.rule;

import com.beaver.drools.common.model.RuleResult;
import com.google.common.base.Splitter;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.tuple.Pair;

import java.util.*;
import java.util.Map.Entry;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.stream.Collectors;

/**
 * Created by beaver on 2017/5/20.

 * 简单规则组成,并不不包含drools复杂的语法规则
 */
public class TravelRuleGenerate {
    //规则包名
    private String packageName;
    //规则需要外部类的包
    private List importPackages = new ArrayList<>();
    //规则名字
    private String ruleName;
    
    //规则匹配的类型，如 $o: OrderItem( $p : price, $code : custCode )中的OrderItem
    private String objectType;
    
    //规则匹配类型的变量名，如 $o: OrderItem( $p : price, $code : custCode )中的OrderItem中$o
    private String objectVar;
    
    //规则信息
    private TravelRule travelRule;
    
    //规则执行动作结果赋值属性名，如 $invoice.setResult(RuleResult.REJECT); 中的resultr;
    private String resultPropertyName;
    //规则执行动作结果的提示信息赋值属性名，如   $invoice.setRemarkMessage("您的房费高于公司标准 ");中的remarkMessage.
    private String alertMessagePropertyName;
    
    //规则匹配属性别名，如data["EXPENSE_LEVEL"] not in ("总裁"),
    // 中的EXPENSE_LEVEL在travelRule中droolsRule中的名不一样，类似mybatis映射一下
    //不过key为正则表达式
    private Map rulePropertyNameAlias = new HashMap<>();
    
    public String getPackageName() {
        return packageName;
    }
    
    public void setPackageName(String packageName) {
        this.packageName = packageName;
    }
    
    public List getImportPackages() {
        return importPackages;
    }
    
    public void setImportPackages(List importPackages) {
        this.importPackages = importPackages;
    }
    
    public String getRuleName() {
        return ruleName;
    }
    
    public void setRuleName(String ruleName) {
        this.ruleName = ruleName;
    }
    
    public TravelRule getTravelRule() {
        return travelRule;
    }
    
    public void setTravelRule(TravelRule travelRule) {
        this.travelRule = travelRule;
    }
    
    public String getObjectType() {
        return objectType;
    }
    
    public void setObjectType(String objectType) {
        this.objectType = objectType;
    }
    
    public String getObjectVar() {
        return objectVar;
    }
    
    public void setObjectVar(String objectVar) {
        this.objectVar = objectVar;
    }
    
    public String getResultPropertyName() {
        return resultPropertyName;
    }
    
    public void setResultPropertyName(String resultPropertyName) {
        this.resultPropertyName = resultPropertyName;
    }
    
    public String getAlertMessagePropertyName() {
        return alertMessagePropertyName;
    }
    
    public void setAlertMessagePropertyName(String alertMessagePropertyName) {
        this.alertMessagePropertyName = alertMessagePropertyName;
    }
    
    public Map getRulePropertyNameAlias() {
        return rulePropertyNameAlias;
    }
    
    public void setRulePropertyNameAlias(Map rulePropertyNameAlias) {
        this.rulePropertyNameAlias = rulePropertyNameAlias;
    }
    
    //规则生成
    public String Generate() {
        StringBuilder sb = new StringBuilder();
        
        //规则头部
        sb.append("package ").append(packageName).append("\n").append("\n");
        
        importPackages.stream().forEach(t -> sb.append("import ").append(t).append("\n"));
        
        sb.append("\n\n");
        
        //规则名称
        sb.append("rule  \"").append(generateRuleName()).append("\n\n");
        
        //规则条件
        sb.append("when").append("\n");
        sb.append("  ").append(objectVar).append(" : ").append(objectType).append("(").append("\n");
        
        //规则条件内容
        List rules = generateWhenContent();
        rules.stream().forEach(t -> {
            sb.append("  ").append(t).append(",\n");
        });
        
        int lastIndexOf = sb.lastIndexOf(",");
        if (lastIndexOf > 0) {
            sb.deleteCharAt(lastIndexOf);
        }
        
        sb.append(" ) \n");
        
        
        //规则执行动作
        sb.append("then \n");
        
        //规则执行结果
        sb.append("  ").append(objectVar).append(".set").append(StringUtils.capitalize(resultPropertyName)).append("(");
        RuleResult ruleResult = RuleResult.valueOf(travelRule.getRuleAction());
        sb.append(RuleResult.class.getSimpleName()).append(".").append(ruleResult.name()).append("); \n");
        
        //规则执行提示信息
        sb.append("  ").append(objectVar).append(".set").append(StringUtils.capitalize(alertMessagePropertyName)).append("(\"");
        sb.append(travelRule.getAlertMessage()).append(" \");");
        
        sb.append("\n").append("end");
        return sb.toString();
    }
    
    //{EXP_LEVEL}IN[一般员工] AND {ER_LOCATION}NOT IN[北京/上海/深圳] AND {ER_EXP_FEE}>{ER_DAYS}*300
    private List generateWhenContent() {
        String rule = travelRule.getRule().trim();
        if (rule.contains("OR") || rule.contains("or")) {
            throw new UnsupportedOperationException("请知悉drools 的基本使用：复杂的规则拆成简单的规则执行，or的规则请拆分");
        }
        
        if (rule.contains("and")) {
            throw new UnsupportedOperationException("AND条件单词大写");
        }
        
        
        List ruelList = Splitter.on(Pattern.compile("AND")).trimResults().splitToList(rule);
        
        List rules = ruelList.stream().map(this::generateARule).collect(Collectors.toList());
        return rules;
    }
    
    //去除AND条件的一条简单规则
    private String generateARule(final String rule) {
        if (StringUtils.deleteWhitespace(rule).contains("NOTIN")) {
            Pair pair = getRulePropertyNameAliasAndValuesForIn(rule, "NOT");
            return pair.getKey() + " not in " + pair.getValue();
        }
        
        if (rule.contains("IN")) {
            Pair pair = getRulePropertyNameAliasAndValuesForIn(rule, "IN");
            return pair.getKey() + " in " + pair.getValue();
        }
        
        if (rule.contains(">")) {
            return getRulePropertyNameAliasAndValuesForCompare(rule, ">");
        }
        
        throw new UnsupportedOperationException();
    }
    
    //{EXP_LEVEL}IN[一般员工] , {ER_LOCATION}NOT IN[北京/上海/深圳]  to
    //data["EXPENSE_LEVEL"] in ("一般员工"),	data["city"] not in ("上海","北京","深圳","广州"),
    private Pair getRulePropertyNameAliasAndValuesForIn(final String rule, final String separators) {
        String name = StringUtils.splitByWholeSeparator(rule, separators)[0];
        name = getRulePropertyNameAlias(name).getValue();
        
        name = "data[\"" + name + "\"]";
        
        String value = StringUtils.substring(rule
                , StringUtils.lastIndexOf(rule, "[") + 1
                , StringUtils.lastIndexOf(rule, "]"));
        
        List values = Splitter.on("/").trimResults().splitToList(value);
        value = values.stream().map(t -> "\"" + t + "\"").collect(Collectors.joining(","));
        value = "(" + value + ")";
        return Pair.of(name, value);
    }
    
    //{ER_EXP_FEE}>{ER_DAYS}*300     to
    // BigDecimal.valueOf(Double.valueOf(data.["INVOICE_AMOUNT"])) > 300 * Double.valueOf(data["days"])
    private String getRulePropertyNameAliasAndValuesForCompare(final String rule, final String separator) {
        if (!Arrays.asList(">", "<", "=").contains(separator.trim())) {
            throw new UnsupportedOperationException();
        }
        
        List list = Splitter.on(separator.trim()).trimResults().splitToList(rule);
        String express1 = list.get(0);
        String express2 = list.get(1);
        String template1 = "BigDecimal.valueOf(Double.valueOf(data[\"%s\"]))";
        String tempalte2 = "Double.valueOf(data[\"%s\"])";
        
        Pair rulePropertyNameAlias1 = getRulePropertyNameAlias(express1);
        express1 = String.format(template1, rulePropertyNameAlias1.getValue());
        
        Pair rulePropertyNameAlias2 = getRulePropertyNameAlias(express2);
        
        express2 = String.format(tempalte2, rulePropertyNameAlias2.getValue());
        
        String replace = rule.replace(rulePropertyNameAlias1.getKey(), express1);
        replace = replace.replace(rulePropertyNameAlias2.getKey(), express2);
        return replace;
    }
    
    private Pair getRulePropertyNameAlias(final String content) {
        for (Entry entry : rulePropertyNameAlias.entrySet()) {
            Pattern compile = Pattern.compile(entry.getKey());
            Matcher matcher = compile.matcher(content);
            if (matcher.find()) {
                String name = content.substring(matcher.regionStart(), matcher.regionEnd());
                String aliasName = entry.getValue();
                return Pair.of(name, aliasName);
            }
        }
        
        throw new UnsupportedOperationException(content);
    }
    
    private String generateRuleName() {
        StringBuilder sb = new StringBuilder();
        sb.append(travelRule.getCompanyName())
          .append("-")
          .append(travelRule.getExpenseType())
          .append("-")
          .append(ruleName).append("\"");
        
        return sb.toString();
    }
    
}

其中

 //规则生成
    public String Generate() {。。。}

方法主要是drools规则组装的实现。

我们测试一下：

package com.beaver.drools.exampl.travel.rule;

import com.beaver.drools.util.KieSessionUtil;
import com.google.gson.Gson;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.javafunk.excelparser.SheetParser;
import org.kie.api.io.ResourceType;

import java.io.IOException;
import java.io.InputStream;
import java.util.*;
import java.util.stream.Collectors;

/**
 * Created by beaver on 2017/5/20.
 */
public class TravleRuelTest {
    
    static String packageName = "com.beaver.drools.exampl.travel.rule";
    static List importPackages = Arrays.asList(
            "java.math.*"
            , "com.beaver.drools.common.model.*");
    
    
    static String sheetName = "工作表1";
    static String fileName = "腾讯差标规则1.xlsx";
    
    static String objectType = "MatchInvoiceTravelRuleRequestDto";
    static String objectVar = "$invoice";
    
    static String resultPropertyName = "result";
    static String alertMessagePropertyName = "remarkMessage";
    
    //规则内容属性别名，如{EXP_LEVEL}IN[一般员工]，EXP_LEVEL 可以起别名
    static Map rulePropertyNameAlias = new HashMap<>();
    
    static {
        rulePropertyNameAlias.put("\\{.*LEVEL.*\\}", "EXPENSE_LEVEL");
        rulePropertyNameAlias.put("\\{.*LOCATION.*\\}", "city");
        rulePropertyNameAlias.put("\\{.*FEE.*\\}", "INVOICE_AMOUNT");
        rulePropertyNameAlias.put("\\{.*DAYS.*\\}", "days");
    }
    
    public static void main(String[] args) throws IOException {
        //Get the sheet using POI API.
        SheetParser parser = new SheetParser();
        InputStream inputStream = TravleRuelTest.class.getClassLoader().getResourceAsStream(fileName);
        Sheet sheet = new XSSFWorkbook(inputStream).getSheet(sheetName);
        //Invoke the Sheet parser.
        List entityList = parser.createEntity(sheet, TravelRule.class, t -> t.printStackTrace());
        
        //
        entityList = entityList.stream()
                               .filter(t -> t.getCompanyName() != null && !t.getCompanyName().isEmpty())
                               .collect(Collectors.toList());
        
        
        System.out.println(new Gson().toJson(entityList));
        
        Set set = entityList.stream().map(TravelRule::getRuleId).collect(Collectors.toSet());
        if (set.size() != entityList.size()) {
            throw new IllegalArgumentException("id 有重复");
        }
        
        
        entityList.stream()
                  .map(TravleRuelTest::travelRuleGenerate)
                  .forEach(t -> {
                      System.out.println(t);
                  });
    }
    
    
    public static TravelRule travelRuleGenerate(TravelRule travelRule) {
        TravelRuleGenerate travelRuleGenerate = new TravelRuleGenerate();
        travelRuleGenerate.setPackageName(packageName);
        travelRuleGenerate.setImportPackages(importPackages);
        travelRuleGenerate.setRuleName(travelRule.getRule());
        travelRuleGenerate.setObjectType(objectType);
        travelRuleGenerate.setObjectVar(objectVar);
        travelRuleGenerate.setTravelRule(travelRule);
        travelRuleGenerate.setResultPropertyName(resultPropertyName);
        travelRuleGenerate.setAlertMessagePropertyName(alertMessagePropertyName);
        travelRuleGenerate.setRulePropertyNameAlias(rulePropertyNameAlias);
        String generate = travelRuleGenerate.Generate();
        
        KieSessionUtil kieSessionUtil = new KieSessionUtil();
        kieSessionUtil.addContent(generate, ResourceType.DRL);
        kieSessionUtil.verifyRules();
        travelRule.setDroolsRule(generate);
        return travelRule;
    }
    
}

输出：

..................................
[
  {
    "companyName": "微民",
    "expenseType": "住宿费",
    "applyPoint": "ER_SUBMIT",
    "ruleAction": "REJECT",
    "rule": "{EXP_LEVEL}IN[1] AND {ER_EXP_FEE}\u003e{ER_DAYS} *600",
    "alertMessage": "您的房费高于公司标准",
    "ruleId": "8a24ef78-d1c4-4c7c-924f-f199fa3c5eb1"
  },
  {
    "companyName": "微民",
    "expenseType": "住宿费",
    "applyPoint": "ER_SUBMIT",
    "ruleAction": "REJECT",
    "rule": "{EXP_LEVEL}IN[2] AND {ER_EXP_FEE}\u003e{ER_DAYS}*700",
    "alertMessage": "您的房费高于公司标准",
    "ruleId": "f9b17610-7917-4f71-b369-602224fdd20d"
  },
  {
    "companyName": "微民",
    "expenseType": "住宿费",
    "applyPoint": "ER_SUBMIT",
    "ruleAction": "REJECT",
    "rule": "{EXP_LEVEL}IN[3] AND {ER_EXP_FEE}\u003e{ER_DAYS}*800",
    "alertMessage": "您的房费高于公司标准",
    "ruleId": "128e621a-832a-4876-81c8-a5a9624b6ca7"
  },
  {
    "companyName": "微民",
    "expenseType": "差旅补贴",
    "applyPoint": "ER_SUBMIT",
    "ruleAction": "REJECT",
    "rule": "{ER_LOCATION_COUNTRY}IN[中国] AND {ER_EXP_FEE}\u003e{ER_DAYS}*140",
    "alertMessage": "您的补贴高于公司标准",
    "ruleId": "06d1afc9-4a0e-4ad6-b0b1-01af068997fe"
  },
  {
    "companyName": "微民",
    "expenseType": "差旅补贴",
    "applyPoint": "ER_SUBMIT",
    "ruleAction": "REJECT",
    "rule": "{ER_LOCATION_COUNTRY}NOT IN[中国] AND {ER_EXP_FEE}\u003e{ER_DAYS}*400",
    "alertMessage": "您的补贴高于公司标准",
    "ruleId": "922d99ff-c5bc-4f26-a365-d8b6e8a9a999"
  },
  {
    "companyName": "腾南",
    "expenseType": "住宿费",
    "applyPoint": "ER_SUBMIT",
    "ruleAction": "REJECT",
    "rule": "{EXP_LEVEL}IN[一般员工] AND {ER_EXP_FEE}\u003e{ER_DAYS}*400",
    "alertMessage": "您的房费高于公司标准",
    "ruleId": "7c170ce0-080e-499a-9046-0dc7d226b86c"
  },
  {
    "companyName": "腾南",
    "expenseType": "住宿费",
    "applyPoint": "ER_SUBMIT",
    "ruleAction": "REJECT",
    "rule": "{EXP_LEVEL}IN[一般员工] AND {ER_LOCATION}NOT IN[北京/上海/深圳] AND {ER_EXP_FEE}\u003e{ER_DAYS}*300",
    "alertMessage": "您的房费高于公司标准",
    "ruleId": "6135e677-867b-41ed-8d00-7512b5ec5c2a"
  },
  {
    "companyName": "腾南",
    "expenseType": "住宿费",
    "applyPoint": "ER_SUBMIT",
    "ruleAction": "REJECT",
    "rule": "{EXP_LEVEL}IN[总监] AND {ER_EXP_FEE}\u003e{ER_DAYS}*550",
    "alertMessage": "您的房费高于公司标准",
    "ruleId": "636ebfda-6d78-4ec7-a441-234ff931fa57"
  },
  {
    "companyName": "腾南",
    "expenseType": "住宿费",
    "applyPoint": "ER_SUBMIT",
    "ruleAction": "REJECT",
    "rule": "{EXP_LEVEL}IN[总监] AND {ER_LOCATION}NOT IN[北京/上海/深圳] AND {ER_EXP_FEE}\u003e{ER_DAYS}*400",
    "alertMessage": "您的房费高于公司标准",
    "ruleId": "b236a113-e547-4f65-9ddc-3b9549efa6ce"
  },
  {
    "companyName": "腾南",
    "expenseType": "住宿费",
    "applyPoint": "ER_SUBMIT",
    "ruleAction": "REJECT",
    "rule": "{EXP_LEVEL}IN[总裁] AND {ER_EXP_FEE}\u003e{ER_DAYS}*700",
    "alertMessage": "您的房费高于公司标准",
    "ruleId": "8bb7e480-bf94-4c24-a46e-963ae60bee7e"
  },
  {
    "companyName": "腾南",
    "expenseType": "住宿费",
    "applyPoint": "ER_SUBMIT",
    "ruleAction": "REJECT",
    "rule": "{EXP_LEVEL}IN[总裁] AND {ER_LOCATION}NOT IN[北京/上海/深圳] AND {ER_EXP_FEE}\u003e{ER_DAYS}*500",
    "alertMessage": "您的房费高于公司标准",
    "ruleId": "f74d0d7c-d31d-49d9-84ff-c0889bf37771"
  },
  {
    "companyName": "腾南",
    "expenseType": "差旅补贴",
    "applyPoint": "ER_SUBMIT",
    "ruleAction": "REJECT",
    "rule": "{ER_EXP_FEE}\u003e{ER_DAYS}*80",
    "alertMessage": "您的补贴高于公司标准",
    "ruleId": "154866b0-fdc5-433f-9c3f-640e9a812564"
  },
  {
    "companyName": "腾新",
    "expenseType": "住宿费",
    "applyPoint": "ER_SUBMIT",
    "ruleAction": "REJECT",
    "rule": "{EXP_LEVEL}IN[总裁] AND {ER_EXP_FEE}\u003e{ER_DAYS}*600",
    "alertMessage": "您的房费高于公司标准",
    "ruleId": "e4ece4c7-f9ca-46fc-bb7b-2a4443513daf"
  },
  {
    "companyName": "腾新",
    "expenseType": "住宿费",
    "applyPoint": "ER_SUBMIT",
    "ruleAction": "REJECT",
    "rule": "{EXP_LEVEL}NOT IN[总裁] AND {ER_EXP_FEE}\u003e{ER_DAYS}*500",
    "alertMessage": "您的房费高于公司标准",
    "ruleId": "51768055-8a13-4d44-9c61-e261bcb74149"
  },
  {
    "companyName": "腾新",
    "expenseType": "住宿费",
    "applyPoint": "ER_SUBMIT",
    "ruleAction": "REJECT",
    "rule": "{EXP_LEVEL}NOT IN[总裁] AND {ER_LOCATION}NOT IN[北京/上海/深圳/成都/广州/杭州] AND {ER_EXP_FEE}\u003e{ER_DAYS}*400",
    "alertMessage": "您的房费高于公司标准",
    "ruleId": "0d3f86b6-f937-4544-916d-8fac5061c479"
  },
  {
    "companyName": "腾新",
    "expenseType": "差旅补贴",
    "applyPoint": "ER_SUBMIT",
    "ruleAction": "REJECT",
    "rule": "{ER_EXP_FEE}\u003e{ER_DAYS}*100",
    "alertMessage": "您的补贴高于公司标准",
    "ruleId": "a9c0f423-7880-4f86-a761-ba2f2ec83c66"
  }
]

.....................

TravelRule{companyName='微民', expenseType='住宿费', applyPoint='ER_SUBMIT', ruleAction='REJECT', rule='{EXP_LEVEL}IN[1] AND {ER_EXP_FEE}>{ER_DAYS} *600', alertMessage='您的房费高于公司标准', ruleId='8a24ef78-d1c4-4c7c-924f-f199fa3c5eb1', droolsRule='package com.beaver.drools.exampl.travel.rule

import java.math.*
import com.beaver.drools.common.model.*


rule  "微民-住宿费-{EXP_LEVEL}IN[1] AND {ER_EXP_FEE}>{ER_DAYS} *600"

when
  $invoice : MatchInvoiceTravelRuleRequestDto(
  data["EXPENSE_LEVEL"] in ("1"),
  BigDecimal.valueOf(Double.valueOf(data["INVOICE_AMOUNT"]))>Double.valueOf(data["days"])
 ) 
then 
  $invoice.setResult(RuleResult.REJECT); 
  $invoice.setRemarkMessage("您的房费高于公司标准 ");
end'}
TravelRule{companyName='微民', expenseType='住宿费', applyPoint='ER_SUBMIT', ruleAction='REJECT', rule='{EXP_LEVEL}IN[2] AND {ER_EXP_FEE}>{ER_DAYS}*700', alertMessage='您的房费高于公司标准', ruleId='f9b17610-7917-4f71-b369-602224fdd20d', droolsRule='package com.beaver.drools.exampl.travel.rule

import java.math.*
import com.beaver.drools.common.model.*


rule  "微民-住宿费-{EXP_LEVEL}IN[2] AND {ER_EXP_FEE}>{ER_DAYS}*700"

when
  $invoice : MatchInvoiceTravelRuleRequestDto(
  data["EXPENSE_LEVEL"] in ("2"),
  BigDecimal.valueOf(Double.valueOf(data["INVOICE_AMOUNT"]))>Double.valueOf(data["days"])
 ) 
then 
  $invoice.setResult(RuleResult.REJECT); 
  $invoice.setRemarkMessage("您的房费高于公司标准 ");
end'}
TravelRule{companyName='微民', expenseType='住宿费', applyPoint='ER_SUBMIT', ruleAction='REJECT', rule='{EXP_LEVEL}IN[3] AND {ER_EXP_FEE}>{ER_DAYS}*800', alertMessage='您的房费高于公司标准', ruleId='128e621a-832a-4876-81c8-a5a9624b6ca7', droolsRule='package com.beaver.drools.exampl.travel.rule

import java.math.*
import com.beaver.drools.common.model.*


rule  "微民-住宿费-{EXP_LEVEL}IN[3] AND {ER_EXP_FEE}>{ER_DAYS}*800"

when
  $invoice : MatchInvoiceTravelRuleRequestDto(
  data["EXPENSE_LEVEL"] in ("3"),
  BigDecimal.valueOf(Double.valueOf(data["INVOICE_AMOUNT"]))>Double.valueOf(data["days"])
 ) 
then 
  $invoice.setResult(RuleResult.REJECT); 
  $invoice.setRemarkMessage("您的房费高于公司标准 ");
end'}
TravelRule{companyName='微民', expenseType='差旅补贴', applyPoint='ER_SUBMIT', ruleAction='REJECT', rule='{ER_LOCATION_COUNTRY}IN[中国] AND {ER_EXP_FEE}>{ER_DAYS}*140', alertMessage='您的补贴高于公司标准', ruleId='06d1afc9-4a0e-4ad6-b0b1-01af068997fe', droolsRule='package com.beaver.drools.exampl.travel.rule

import java.math.*
import com.beaver.drools.common.model.*


rule  "微民-差旅补贴-{ER_LOCATION_COUNTRY}IN[中国] AND {ER_EXP_FEE}>{ER_DAYS}*140"

when
  $invoice : MatchInvoiceTravelRuleRequestDto(
  data["city"] in ("中国"),
  BigDecimal.valueOf(Double.valueOf(data["INVOICE_AMOUNT"]))>Double.valueOf(data["days"])
 ) 
then 
  $invoice.setResult(RuleResult.REJECT); 
  $invoice.setRemarkMessage("您的补贴高于公司标准 ");
end'}
TravelRule{companyName='微民', expenseType='差旅补贴', applyPoint='ER_SUBMIT', ruleAction='REJECT', rule='{ER_LOCATION_COUNTRY}NOT IN[中国] AND {ER_EXP_FEE}>{ER_DAYS}*400', alertMessage='您的补贴高于公司标准', ruleId='922d99ff-c5bc-4f26-a365-d8b6e8a9a999', droolsRule='package com.beaver.drools.exampl.travel.rule

import java.math.*
import com.beaver.drools.common.model.*


rule  "微民-差旅补贴-{ER_LOCATION_COUNTRY}NOT IN[中国] AND {ER_EXP_FEE}>{ER_DAYS}*400"

when
  $invoice : MatchInvoiceTravelRuleRequestDto(
  data["city"] not in ("中国"),
  BigDecimal.valueOf(Double.valueOf(data["INVOICE_AMOUNT"]))>Double.valueOf(data["days"])
 ) 
then 
  $invoice.setResult(RuleResult.REJECT); 
  $invoice.setRemarkMessage("您的补贴高于公司标准 ");
end'}
TravelRule{companyName='腾南', expenseType='住宿费', applyPoint='ER_SUBMIT', ruleAction='REJECT', rule='{EXP_LEVEL}IN[一般员工] AND {ER_EXP_FEE}>{ER_DAYS}*400', alertMessage='您的房费高于公司标准', ruleId='7c170ce0-080e-499a-9046-0dc7d226b86c', droolsRule='package com.beaver.drools.exampl.travel.rule

import java.math.*
import com.beaver.drools.common.model.*


rule  "腾南-住宿费-{EXP_LEVEL}IN[一般员工] AND {ER_EXP_FEE}>{ER_DAYS}*400"

when
  $invoice : MatchInvoiceTravelRuleRequestDto(
  data["EXPENSE_LEVEL"] in ("一般员工"),
  BigDecimal.valueOf(Double.valueOf(data["INVOICE_AMOUNT"]))>Double.valueOf(data["days"])
 ) 
then 
  $invoice.setResult(RuleResult.REJECT); 
  $invoice.setRemarkMessage("您的房费高于公司标准 ");
end'}
TravelRule{companyName='腾南', expenseType='住宿费', applyPoint='ER_SUBMIT', ruleAction='REJECT', rule='{EXP_LEVEL}IN[一般员工] AND {ER_LOCATION}NOT IN[北京/上海/深圳] AND {ER_EXP_FEE}>{ER_DAYS}*300', alertMessage='您的房费高于公司标准', ruleId='6135e677-867b-41ed-8d00-7512b5ec5c2a', droolsRule='package com.beaver.drools.exampl.travel.rule

import java.math.*
import com.beaver.drools.common.model.*


rule  "腾南-住宿费-{EXP_LEVEL}IN[一般员工] AND {ER_LOCATION}NOT IN[北京/上海/深圳] AND {ER_EXP_FEE}>{ER_DAYS}*300"

when
  $invoice : MatchInvoiceTravelRuleRequestDto(
  data["EXPENSE_LEVEL"] in ("一般员工"),
  data["city"] not in ("北京","上海","深圳"),
  BigDecimal.valueOf(Double.valueOf(data["INVOICE_AMOUNT"]))>Double.valueOf(data["days"])
 ) 
then 
  $invoice.setResult(RuleResult.REJECT); 
  $invoice.setRemarkMessage("您的房费高于公司标准 ");
end'}
TravelRule{companyName='腾南', expenseType='住宿费', applyPoint='ER_SUBMIT', ruleAction='REJECT', rule='{EXP_LEVEL}IN[总监] AND {ER_EXP_FEE}>{ER_DAYS}*550', alertMessage='您的房费高于公司标准', ruleId='636ebfda-6d78-4ec7-a441-234ff931fa57', droolsRule='package com.beaver.drools.exampl.travel.rule

import java.math.*
import com.beaver.drools.common.model.*


rule  "腾南-住宿费-{EXP_LEVEL}IN[总监] AND {ER_EXP_FEE}>{ER_DAYS}*550"

when
  $invoice : MatchInvoiceTravelRuleRequestDto(
  data["EXPENSE_LEVEL"] in ("总监"),
  BigDecimal.valueOf(Double.valueOf(data["INVOICE_AMOUNT"]))>Double.valueOf(data["days"])
 ) 
then 
  $invoice.setResult(RuleResult.REJECT); 
  $invoice.setRemarkMessage("您的房费高于公司标准 ");
end'}
TravelRule{companyName='腾南', expenseType='住宿费', applyPoint='ER_SUBMIT', ruleAction='REJECT', rule='{EXP_LEVEL}IN[总监] AND {ER_LOCATION}NOT IN[北京/上海/深圳] AND {ER_EXP_FEE}>{ER_DAYS}*400', alertMessage='您的房费高于公司标准', ruleId='b236a113-e547-4f65-9ddc-3b9549efa6ce', droolsRule='package com.beaver.drools.exampl.travel.rule

import java.math.*
import com.beaver.drools.common.model.*


rule  "腾南-住宿费-{EXP_LEVEL}IN[总监] AND {ER_LOCATION}NOT IN[北京/上海/深圳] AND {ER_EXP_FEE}>{ER_DAYS}*400"

when
  $invoice : MatchInvoiceTravelRuleRequestDto(
  data["EXPENSE_LEVEL"] in ("总监"),
  data["city"] not in ("北京","上海","深圳"),
  BigDecimal.valueOf(Double.valueOf(data["INVOICE_AMOUNT"]))>Double.valueOf(data["days"])
 ) 
then 
  $invoice.setResult(RuleResult.REJECT); 
  $invoice.setRemarkMessage("您的房费高于公司标准 ");
end'}
TravelRule{companyName='腾南', expenseType='住宿费', applyPoint='ER_SUBMIT', ruleAction='REJECT', rule='{EXP_LEVEL}IN[总裁] AND {ER_EXP_FEE}>{ER_DAYS}*700', alertMessage='您的房费高于公司标准', ruleId='8bb7e480-bf94-4c24-a46e-963ae60bee7e', droolsRule='package com.beaver.drools.exampl.travel.rule

import java.math.*
import com.beaver.drools.common.model.*


rule  "腾南-住宿费-{EXP_LEVEL}IN[总裁] AND {ER_EXP_FEE}>{ER_DAYS}*700"

when
  $invoice : MatchInvoiceTravelRuleRequestDto(
  data["EXPENSE_LEVEL"] in ("总裁"),
  BigDecimal.valueOf(Double.valueOf(data["INVOICE_AMOUNT"]))>Double.valueOf(data["days"])
 ) 
then 
  $invoice.setResult(RuleResult.REJECT); 
  $invoice.setRemarkMessage("您的房费高于公司标准 ");
end'}
TravelRule{companyName='腾南', expenseType='住宿费', applyPoint='ER_SUBMIT', ruleAction='REJECT', rule='{EXP_LEVEL}IN[总裁] AND {ER_LOCATION}NOT IN[北京/上海/深圳] AND {ER_EXP_FEE}>{ER_DAYS}*500', alertMessage='您的房费高于公司标准', ruleId='f74d0d7c-d31d-49d9-84ff-c0889bf37771', droolsRule='package com.beaver.drools.exampl.travel.rule

import java.math.*
import com.beaver.drools.common.model.*


rule  "腾南-住宿费-{EXP_LEVEL}IN[总裁] AND {ER_LOCATION}NOT IN[北京/上海/深圳] AND {ER_EXP_FEE}>{ER_DAYS}*500"

when
  $invoice : MatchInvoiceTravelRuleRequestDto(
  data["EXPENSE_LEVEL"] in ("总裁"),
  data["city"] not in ("北京","上海","深圳"),
  BigDecimal.valueOf(Double.valueOf(data["INVOICE_AMOUNT"]))>Double.valueOf(data["days"])
 ) 
then 
  $invoice.setResult(RuleResult.REJECT); 
  $invoice.setRemarkMessage("您的房费高于公司标准 ");
end'}
TravelRule{companyName='腾南', expenseType='差旅补贴', applyPoint='ER_SUBMIT', ruleAction='REJECT', rule='{ER_EXP_FEE}>{ER_DAYS}*80', alertMessage='您的补贴高于公司标准', ruleId='154866b0-fdc5-433f-9c3f-640e9a812564', droolsRule='package com.beaver.drools.exampl.travel.rule

import java.math.*
import com.beaver.drools.common.model.*


rule  "腾南-差旅补贴-{ER_EXP_FEE}>{ER_DAYS}*80"

when
  $invoice : MatchInvoiceTravelRuleRequestDto(
  BigDecimal.valueOf(Double.valueOf(data["INVOICE_AMOUNT"]))>Double.valueOf(data["days"])
 ) 
then 
  $invoice.setResult(RuleResult.REJECT); 
  $invoice.setRemarkMessage("您的补贴高于公司标准 ");
end'}
TravelRule{companyName='腾新', expenseType='住宿费', applyPoint='ER_SUBMIT', ruleAction='REJECT', rule='{EXP_LEVEL}IN[总裁] AND {ER_EXP_FEE}>{ER_DAYS}*600', alertMessage='您的房费高于公司标准', ruleId='e4ece4c7-f9ca-46fc-bb7b-2a4443513daf', droolsRule='package com.beaver.drools.exampl.travel.rule

import java.math.*
import com.beaver.drools.common.model.*


rule  "腾新-住宿费-{EXP_LEVEL}IN[总裁] AND {ER_EXP_FEE}>{ER_DAYS}*600"

when
  $invoice : MatchInvoiceTravelRuleRequestDto(
  data["EXPENSE_LEVEL"] in ("总裁"),
  BigDecimal.valueOf(Double.valueOf(data["INVOICE_AMOUNT"]))>Double.valueOf(data["days"])
 ) 
then 
  $invoice.setResult(RuleResult.REJECT); 
  $invoice.setRemarkMessage("您的房费高于公司标准 ");
end'}
TravelRule{companyName='腾新', expenseType='住宿费', applyPoint='ER_SUBMIT', ruleAction='REJECT', rule='{EXP_LEVEL}NOT IN[总裁] AND {ER_EXP_FEE}>{ER_DAYS}*500', alertMessage='您的房费高于公司标准', ruleId='51768055-8a13-4d44-9c61-e261bcb74149', droolsRule='package com.beaver.drools.exampl.travel.rule

import java.math.*
import com.beaver.drools.common.model.*


rule  "腾新-住宿费-{EXP_LEVEL}NOT IN[总裁] AND {ER_EXP_FEE}>{ER_DAYS}*500"

when
  $invoice : MatchInvoiceTravelRuleRequestDto(
  data["EXPENSE_LEVEL"] not in ("总裁"),
  BigDecimal.valueOf(Double.valueOf(data["INVOICE_AMOUNT"]))>Double.valueOf(data["days"])
 ) 
then 
  $invoice.setResult(RuleResult.REJECT); 
  $invoice.setRemarkMessage("您的房费高于公司标准 ");
end'}
TravelRule{companyName='腾新', expenseType='住宿费', applyPoint='ER_SUBMIT', ruleAction='REJECT', rule='{EXP_LEVEL}NOT IN[总裁] AND {ER_LOCATION}NOT IN[北京/上海/深圳/成都/广州/杭州] AND {ER_EXP_FEE}>{ER_DAYS}*400', alertMessage='您的房费高于公司标准', ruleId='0d3f86b6-f937-4544-916d-8fac5061c479', droolsRule='package com.beaver.drools.exampl.travel.rule

import java.math.*
import com.beaver.drools.common.model.*


rule  "腾新-住宿费-{EXP_LEVEL}NOT IN[总裁] AND {ER_LOCATION}NOT IN[北京/上海/深圳/成都/广州/杭州] AND {ER_EXP_FEE}>{ER_DAYS}*400"

when
  $invoice : MatchInvoiceTravelRuleRequestDto(
  data["EXPENSE_LEVEL"] not in ("总裁"),
  data["city"] not in ("北京","上海","深圳","成都","广州","杭州"),
  BigDecimal.valueOf(Double.valueOf(data["INVOICE_AMOUNT"]))>Double.valueOf(data["days"])
 ) 
then 
  $invoice.setResult(RuleResult.REJECT); 
  $invoice.setRemarkMessage("您的房费高于公司标准 ");
end'}
TravelRule{companyName='腾新', expenseType='差旅补贴', applyPoint='ER_SUBMIT', ruleAction='REJECT', rule='{ER_EXP_FEE}>{ER_DAYS}*100', alertMessage='您的补贴高于公司标准', ruleId='a9c0f423-7880-4f86-a761-ba2f2ec83c66', droolsRule='package com.beaver.drools.exampl.travel.rule

import java.math.*
import com.beaver.drools.common.model.*


rule  "腾新-差旅补贴-{ER_EXP_FEE}>{ER_DAYS}*100"

when
  $invoice : MatchInvoiceTravelRuleRequestDto(
  BigDecimal.valueOf(Double.valueOf(data["INVOICE_AMOUNT"]))>Double.valueOf(data["days"])
 ) 
then 
  $invoice.setResult(RuleResult.REJECT); 
  $invoice.setRemarkMessage("您的补贴高于公司标准 ");
end'}

Process finished with exit code 0

 每产生一个规则，都用drools引擎校验了一下，以防出错。

 上面只是对简单的规则如：

{EXP_LEVEL}NOT IN[总裁] AND {ER_LOCATION}NOT IN[北京/上海/深圳/成都/广州/杭州] AND {ER_EXP_FEE}>{ER_DAYS}*400

 做了解析，用的是比较笨的解析和组装，复杂的或者本文是不是可以用

https://github.com/antlr/antlr4
https://github.com/antlr/stringtemplate4
http://freemarker.org

这些工具更简单呢，后面学习一下第一个工具，再试试。

本文代码地址：

https://github.com/sdcuike/drools-example/tree/2017-05-21/src/main/java/com/beaver/drools/exampl/travel/rule