drools - 如何在流口水时编写嵌套条件

Question

这是我的 JSON 文档

    {
   "location": {
      "details": [
         {
            "country": "India",
            "state": "haryana"
         },
         {
            "country": "America",
            "state": "LA"
         },
         {
            "country": "India",
            "state": "Maharashtra"
         }
      ]
   },
   "organisation": {
      "details": [
         {
            "name": "AON",
            "country": "india"
         },
         {
            "name": "AON",
            "country": "America"
         }
      ]
   }
}

我必须应用以下格式的规则

 If(

        (location.details.country=='India' OR 
        location.details.state=='haryana') 
AND 

        organisation.details.name=='AON'
    )

到目前为止，我已经研究并知道 领域的规则可以以嵌套格式应用相同的类，如下所示 .在此链接中: How to write nested conditions in when in drools

// Use this instead
Person( ( age > 50 && weight > 80 ) || height > 2 )

但我想在相同的嵌套条件下应用不同 pojo 类的规则，如下所示

    If(

                (location.details.country=='India' OR 
                location.details.state=='haryana') 
        AND 

                organisation.details.name=='AON'
      AND 
               (location.details.country=='India' AND
                organisation.details.country=='India')
            )
//any level of nested between different pojo classes can be present

这可以在流口水中做到吗？

我写了以下规则

rule "rule1"
salience 1
when


        $rootDoc:RootDoc($locationList:location && $organisationList:organisation) 

     and
        (
            $orgList:Organisation($orgdetailsList:details) from $organisationList
            NamesList1:Details(name=='AON') from $orgdetailsList
            or
            $locList:Location($locdetailsList:details) from $locationList
            NamesList2:Details_(state=='haryana') from $locdetailsList

        )

then
    System.out.println("Pojo Welocome-------");



end

但它向我显示了这个错误: 规则“rule1”中的第 18:3 行不匹配输入“NamesList1”

基本上，当我在同一个括号中写两个条件时，它向我显示错误。

以下是 pojo 类

-----------------------------------pojo_Classes2.Detail.java-----------------------------------

package pojo_Classes2;

import java.util.HashMap;
import java.util.Map;
import com.fasterxml.jackson.annotation.JsonAnyGetter;
import com.fasterxml.jackson.annotation.JsonAnySetter;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonPropertyOrder;

@JsonInclude(JsonInclude.Include.NON_NULL)
@JsonPropertyOrder({
"name",
"country"
})
public class Detail {

@JsonProperty("name")
private String name;
@JsonProperty("country")
private String country;
@JsonIgnore
private Map<String, Object> additionalProperties = new HashMap<String, Object>();

@JsonProperty("name")
public String getName() {
return name;
}

@JsonProperty("name")
public void setName(String name) {
this.name = name;
}

@JsonProperty("country")
public String getCountry() {
return country;
}

@JsonProperty("country")
public void setCountry(String country) {
this.country = country;
}

@JsonAnyGetter
public Map<String, Object> getAdditionalProperties() {
return this.additionalProperties;
}

@JsonAnySetter
public void setAdditionalProperty(String name, Object value) {
this.additionalProperties.put(name, value);
}

}
-----------------------------------pojo_Classes2.Detail_.java-----------------------------------

package pojo_Classes2;

import java.util.HashMap;
import java.util.Map;
import com.fasterxml.jackson.annotation.JsonAnyGetter;
import com.fasterxml.jackson.annotation.JsonAnySetter;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonPropertyOrder;

@JsonInclude(JsonInclude.Include.NON_NULL)
@JsonPropertyOrder({
"country",
"state"
})
public class Detail_ {

@JsonProperty("country")
private String country;
@JsonProperty("state")
private String state;
@JsonIgnore
private Map<String, Object> additionalProperties = new HashMap<String, Object>();

@JsonProperty("country")
public String getCountry() {
return country;
}

@JsonProperty("country")
public void setCountry(String country) {
this.country = country;
}

@JsonProperty("state")
public String getState() {
return state;
}

@JsonProperty("state")
public void setState(String state) {
this.state = state;
}

@JsonAnyGetter
public Map<String, Object> getAdditionalProperties() {
return this.additionalProperties;
}

@JsonAnySetter
public void setAdditionalProperty(String name, Object value) {
this.additionalProperties.put(name, value);
}

}
-----------------------------------pojo_Classes2.Location.java-----------------------------------

package pojo_Classes2;

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import com.fasterxml.jackson.annotation.JsonAnyGetter;
import com.fasterxml.jackson.annotation.JsonAnySetter;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonPropertyOrder;

@JsonInclude(JsonInclude.Include.NON_NULL)
@JsonPropertyOrder({
"details"
})
public class Location {

@JsonProperty("details")
private List<Detail_> details = null;
@JsonIgnore
private Map<String, Object> additionalProperties = new HashMap<String, Object>();

@JsonProperty("details")
public List<Detail_> getDetails() {
return details;
}

@JsonProperty("details")
public void setDetails(List<Detail_> details) {
this.details = details;
}

@JsonAnyGetter
public Map<String, Object> getAdditionalProperties() {
return this.additionalProperties;
}

@JsonAnySetter
public void setAdditionalProperty(String name, Object value) {
this.additionalProperties.put(name, value);
}

}
-----------------------------------pojo_Classes2.Organisation.java-----------------------------------

package pojo_Classes2;

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import com.fasterxml.jackson.annotation.JsonAnyGetter;
import com.fasterxml.jackson.annotation.JsonAnySetter;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonPropertyOrder;

@JsonInclude(JsonInclude.Include.NON_NULL)
@JsonPropertyOrder({
"details"
})
public class Organisation {

@JsonProperty("details")
private List<Detail> details = null;
@JsonIgnore
private Map<String, Object> additionalProperties = new HashMap<String, Object>();

@JsonProperty("details")
public List<Detail> getDetails() {
return details;
}

@JsonProperty("details")
public void setDetails(List<Detail> details) {
this.details = details;
}

@JsonAnyGetter
public Map<String, Object> getAdditionalProperties() {
return this.additionalProperties;
}

@JsonAnySetter
public void setAdditionalProperty(String name, Object value) {
this.additionalProperties.put(name, value);
}

}
-----------------------------------pojo_Classes2.RootDoc.java-----------------------------------

package pojo_Classes2;

import java.util.HashMap;
import java.util.Map;
import com.fasterxml.jackson.annotation.JsonAnyGetter;
import com.fasterxml.jackson.annotation.JsonAnySetter;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonPropertyOrder;

@JsonInclude(JsonInclude.Include.NON_NULL)
@JsonPropertyOrder({
"organisation",
"location"
})
public class RootDoc {

@JsonProperty("organisation")
private Organisation organisation;
@JsonProperty("location")
private Location location;
@JsonIgnore
private Map<String, Object> additionalProperties = new HashMap<String, Object>();

@JsonProperty("organisation")
public Organisation getOrganisation() {
return organisation;
}

@JsonProperty("organisation")
public void setOrganisation(Organisation organisation) {
this.organisation = organisation;
}

@JsonProperty("location")
public Location getLocation() {
return location;
}

@JsonProperty("location")
public void setLocation(Location location) {
this.location = location;
}

@JsonAnyGetter
public Map<String, Object> getAdditionalProperties() {
return this.additionalProperties;
}

@JsonAnySetter
public void setAdditionalProperty(String name, Object value) {
this.additionalProperties.put(name, value);
}

}

我想我找到了问题所在。

这样对吗？

发生这种情况是因为如果条件为它们之间的 OR，您无法绑定(bind)变量并在 RHS 中使用它。？？？

Answer 1

是的，这是完全可能的。

为简单起见，我假设您放入工作内存的对象的结构如下:

class Data {
  Location location;
  Organization organization;
}

子类定义如下:

class Location {
  List<Detail> details;
}
class Organization {
  List<Detail> details;
}
class Detail {
  String name;
  String country;
  String state;
}

这应该准确地为您的问题中的 JSON 建模。为简洁起见，省略了这些类的 getter 和 setter。

现在，我们的目标是编写一个在存在 Detail 时触发的规则。在 Location 内有两个国家=“印度”和国家=“哈里亚纳邦”；还有一个 Detail在 Organization 内名称为“AON”。

我们可以按如下方式完成:

rule "Trigger when Haryana, India is a Location and AON is an Organization name"
when
  // First we need to extract the location and organization so we can do work on them
  Data( $location: location != null,
        $organization: organization != null )

  // Confirm that there exists an organization detail with name = "AON"
  Organization( $orgDetails: details != null ) from $organization
  exists( Detail( name == "AON" ) from $orgDetails )

  // Confirm that there exists a location with country = India and state = Haryana
  Location( $locDetails: details != null ) from $location
  exists( Detail( country == "India", state == "Haryana" ) from $locDetails )
then
  System.out.println("Rule has been executed")
end

我正在使用 exists谓词，因为我只是在检查这些满足条件的对象是否存在。如果我们想将识别的对象绑定(bind)到变​​量，你可以简单地做一个赋值——例如:

// This snippet matches the previous rule where we identify an Organization detail with name of "AON"
Organization( $ordDetails: details != null ) from $organization
$aon: Detail( name == "AON" ) from $orgDetails

甚至自己分配属性:

// This snippet matches the previous rule where we identify the Location detail for Haryana, India
Location( $locDetails: details != null ) from $location
Detail( country == "India",
        state == "Haryana",
        $name: name ) from $locDetails

我对 jackson 的绑定(bind)库不是很熟悉，但是根据我对您发布的 POJO 的理解，对于您直接使用的对象，语法应该非常相似，如果不相同的话。 (据我所知，您的“RootDoc”和我的“数据”实际上是一回事。)

无论如何，这是可行的，因为 Drools 评估所有左侧条件以确定是否应该触发规则。因此，如果我们查看示例规则，它会检查组织内部是否存在满足我们条件的详细信息(名称为“AON”)。如果不满足此条件，则不会触发规则，因为此时左侧已评估为“假”。如果确实存在，我们然后检查 Location 内部是否有满足我们条件的详细信息(同时具有国家 = 印度和州 = 哈里亚纳邦)。该规则只有在左侧的所有条件都满足时才会触发；它是一组“自然”的anded条件。

我认为值得指出的是，必须在同一个谓词中同时检查 country = India 和 state = Haryana。否则，它可能最终会出现这样一种情况，即您有两个细节，每个细节都有一半的条件，但没有一个细节同时具有这两个条件。例如，您可能有一个国家为空但州为哈里亚纳邦的细节，以及一个国家为印度而国家为马哈拉施特拉邦的细节；如果您没有在同一个谓词中进行两项检查，则即使您没有一个 Detail 满足这两个条件，这种情况也可能会触发规则。