基于Drools的规则引擎实例（完整、可运行eclipse工程）

package org.drools.examples; import java.io.Reader; import java.util.ArrayList; import java.util.Date; import java.util.List; import org.drools.QueryResults; import org.drools.RuleBase; import org.drools.RuleBaseFactory; import org.drools.StatefulSession; import org.drools.compiler.PackageBuilder; import org.drools.io.ResourceFactory; import org.drools.rule.Package; import org.drools.spi.Activation; /** * This is a sample file to launch a rule package from a rule source file. */ public class HelloWorldExample { public static void main(String[] args) throws Exception { // 设置系统时间格式 System.setProperty("drools.dateformat", "yyyy-MM-dd HH:mm:ss"); //String filepath = "D:/workspace2/DroolsDemo/src/org/drools/examples/HelloWorld.drl"; final Reader source = ResourceFactory.newClassPathResource("Practise.drl").getReader(); //final Reader source2 = new FileReader(filepath); // final PackageBuilderConfiguration configuration = new PackageBuilderConfiguration(); final PackageBuilder builder = new PackageBuilder(); // this will parse and compile in one step builder.addPackageFromDrl(source); //builder.addPackageFromDrl(source2); // Check the builder for errors if (builder.hasErrors()) { System.out.println("规则脚本存在错误:"+builder.getErrors().toString()); } // get the compiled package (which is serializable) final Package pkg = builder.getPackage(); // add the package to a rulebase (deploy the rule package). final RuleBase ruleBase = RuleBaseFactory.newRuleBase(); Package[] packages = ruleBase.getPackages(); for(Package p :packages){ ruleBase.removePackage(p.getName()); } ruleBase.addPackage(pkg); final StatefulSession session = ruleBase.newStatefulSession(); // session.setGlobal("myGlobalList", new ArrayList<String>()); // session.addEventListener(new DebugAgendaEventListener()); // session.addEventListener(new DebugWorkingMemoryEventListener()); final List<Order> orders = new ArrayList<Order>(); final Order o = new Order(); o.setName("qu"); orders.add(o); final Message message = new Message(); message.setMessage("Hello World"); message.setStatus(Message.HELLO); message.setOrders(orders); message.names.add("网易"); message.setTime(new Date()); message.setStringUtils(new StringUtils()); session.insert(o); session.insert(message); // fire session.fireAllRules(new org.drools.spi.AgendaFilter() { public boolean accept(Activation activation) { return !activation.getRule().getName().contains("_test"); } }); session.dispose(); QueryResults qrs = session.getQueryResults("pcount"); System.out.println(qrs.size()); QueryResults qrs2 = session.getQueryResults("pc2", new Object[]{10}); System.out.println(qrs2.size()); System.out.println("引擎执行完成后："+message.getStatus()+message.getNames()); } public static class Message { public static final int HELLO = 0; public static final int GOODBYE = 1; private String message; private int status; private Date time; private List<Order> orders; private StringUtils stringUtils; public List<String> names = new ArrayList<String>(); public Message() { } public StringUtils getStringUtils() { return stringUtils; } public void setStringUtils(StringUtils stringUtils) { this.stringUtils = stringUtils; } public int getFromDB(){ return stringUtils.getc(); } public String getMessage() { return this.message; } public void setMessage(final String message) { this.message = message; } public int getStatus() { return this.status; } public void setStatus(final int status) { this.status = status; } public List<Order> getOrders() { return orders; } public void setOrders(List<Order> orders) { this.orders = orders; } public List<String> getNames() { return names; } public void setNames(List<String> names) { this.names = names; } public Date getTime() { return time; } public void setTime(Date time) { this.time = time; } } public static class Order { private String name; public String getName() { return name; } public void setName(String name) { this.name = name; } } }