Drools学习（三）实例

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Drools学习（三）实例

(2010-07-10 15:28:11)

在Eclipse新建Drools工程就可以导入自带的例子进行学习。

接下来：

如此，就可以对实例进行学习了。

下面只是参照HelloWorld写的一个小例子，当做笔记。
     设计场景是银行借贷，当借贷款额小于1000时，直接借出，否则，需交由总经理处理。
     1 新建工程，命名：drools,导入Drools相关jar包。
     2 新建Package,命名：aaron.loan，在此包中建立class文件：pojo.java

pojo.java

package aaron.loan;

public class pojo {
int moneycount;

public int getMoneycount() {
return moneycount;
}

public void setMoneycount(int moneycount) {
      this.moneycount = moneycount;
    }

    }

3 新建规则文件：DecisionRule.drl

Decision.drl

import aaron.loan.pojo;
    rule "A"
      when
         $m:pojo(moneycount<1000);
      then
          System.out.println("Done!");
    end

rule "B"
      when
          $m:pojo(moneycount>=1000);
      then
          System.out.println("Pass it to the management!");
    end

4 在aaron.loan包中新建class文件：deploy.java

deploy.java

package aaron.loan;

import org.drools.KnowledgeBase;
    import org.drools.KnowledgeBaseFactory;
    import org.drools.builder.KnowledgeBuilder;
    import org.drools.builder.KnowledgeBuilderError;
    import org.drools.builder.KnowledgeBuilderErrors;
    import org.drools.builder.KnowledgeBuilderFactory;
    import org.drools.builder.ResourceType;
    import org.drools.io.ResourceFactory;
    import org.drools.logger.KnowledgeRuntimeLogger;
    import org.drools.logger.KnowledgeRuntimeLoggerFactory;
    import org.drools.runtime.StatefulKnowledgeSession;

    public class deploy {
     public void loanrool(int moneycount) throws Exception {
       // TODO Auto-generated method stub
             pojo p=new pojo();
          try {
             KnowledgeBase kbase = readKnowledgeBase();
              StatefulKnowledgeSession ksession = kbase.newStatefulKnowledgeSession();
              KnowledgeRuntimeLogger logger = KnowledgeRuntimeLoggerFactory
               .newFileLogger(ksession, "test");

             p.setMoneycount(moneycount);
             ksession.insert(p);
             ksession.fireAllRules();
             System.out.print("moneycount:"+p.getMoneycount());
             logger.close();

          } catch (Throwable t) {
      t.printStackTrace();
    }

   }

private KnowledgeBase readKnowledgeBase() throws Exception {
        KnowledgeBuilder kbuilder = KnowledgeBuilderFactory
           .newKnowledgeBuilder();
        kbuilder.add(ResourceFactory.newClassPathResource("DecisionRule.drl"), ResourceType.DRL);
         KnowledgeBuilderErrors errors = kbuilder.getErrors();
           if (errors.size() > 0) {
                for (KnowledgeBuilderError error : errors) {
                     System.err.println(error);
                            }
         throw new IllegalArgumentException("Could not parse knowledge.");
           }
         KnowledgeBase kbase = KnowledgeBaseFactory.newKnowledgeBase();
           kbase.addKnowledgePackages(kbuilder.getKnowledgePackages());
            return kbase;
        }

}

5 建立测试文件：test.java

test.java

package aaron.loan;

public class test {

      public static void main(String[] args) throws Exception {
           // TODO Auto-generated method stub
            deploy dp=new deploy();
             pojo pj=new pojo();
             pj.setMoneycount(900);   //此处900是任意设的值。
             int mc=pj.getMoneycount();
             dp.loanrool(mc);
       }

}

运行test.java文件，控制台结果如下：

Done!
moneycount:900

到此，Drools小实例就运行成功了 Drools学习（三）实例。