Easy (Batch|Rules) inception #EasyBatch #EasyRules

JobRule.java

import org.easybatch.core.api.Engine;
import org.easyrules.core.BasicRule;

public class JobRule extends BasicRule {

    private ReportHolder reportHolder;

    private ReportPredicate reportPredicate;

    private Engine engine;

    public JobRule(Engine engine, ReportHolder reportHolder, ReportPredicate reportPredicate) {
        super(engine.getName());
        this.engine = engine;
        this.reportHolder = reportHolder;
        this.reportPredicate = reportPredicate;
    }

    @Override
    public boolean evaluate() {
        return reportPredicate.apply(reportHolder.getReport());
    }

    @Override
    public void execute() throws Exception {
        reportHolder.setReport(engine.call());
    }
    
}

ReportHolder.java

import org.easybatch.core.api.Report;

public class ReportHolder {

    private Report report;

    public Report getReport() {
        return report;
    }

    public void setReport(Report report) {
        this.report = report;
    }
}

ReportPredicate.java

import org.easybatch.core.api.Report;

public interface ReportPredicate {
    
    boolean apply(Report report);
    
}

result.txt

INFO: Rule priority threshold: 2,147,483,647
INFO: Skip on first applied rule: false
INFO: Skip on first failed rule: false
INFO: Rule 'engine1ThatFinishesWith100percentSuccess' triggered.
INFO: Initializing the engine
INFO: Engine name: engine1ThatFinishesWith100percentSuccess
INFO: Execution id: bf3267cb-9cad-42cb-8f74-bf62244771d2
INFO: Strict mode: false
INFO: Data source: In-Memory String
INFO: The engine is running
record = [header=[number=1, source="In-Memory String", creationDate="Thu Jun 18 14:16:38 CEST 2015"], payload="foo"]
record = [header=[number=2, source="In-Memory String", creationDate="Thu Jun 18 14:16:38 CEST 2015"], payload="bar"]
INFO: Shutting down the engine
INFO: Rule 'engine1ThatFinishesWith100percentSuccess' performed successfully.
INFO: Rule 'engine2ThatAbortsExecutionOnError' triggered.
INFO: Initializing the engine
INFO: Engine name: engine2ThatAbortsExecutionOnError
INFO: Execution id: 20fa57fa-d11f-43d1-9d30-c6145e894cbc
INFO: Strict mode: true
INFO: Data source: In-Memory String
INFO: The engine is running
SEVERE: An exception occurred while attempting to process record [header=[number=1, source="In-Memory String", creationDate="Thu Jun 18 14:16:38 CEST 2015"], payload="foo"]
org.easybatch.core.api.RecordProcessingException: fatal error!
	at test.Test$2.processRecord(Test.java:32)
	at test.Test$2.processRecord(Test.java:30)
	at org.easybatch.core.impl.ProcessingPipeline.process(ProcessingPipeline.java:66)
	at org.easybatch.core.impl.EngineImpl.call(EngineImpl.java:224)
	at org.easybatch.core.impl.EngineImpl.call(EngineImpl.java:48)
	at test.JobRule.execute(JobRule.java:28)
	at org.easyrules.core.DefaultRulesEngine.applyRules(DefaultRulesEngine.java:138)
	at org.easyrules.core.DefaultRulesEngine.fireRules(DefaultRulesEngine.java:112)
	at test.Test.main(Test.java:59)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)
INFO: Strict mode enabled: aborting execution
INFO: Shutting down the engine
INFO: Rule 'engine2ThatAbortsExecutionOnError' performed successfully.
INFO: Rule 'engine3ThatIsUsedOnlyForTestAndThatWillNotBeCalled' has been evaluated to false, it has not been executed.

ShouldAlwaysBeExecuted.java

import org.easybatch.core.api.Report;

public class ShouldAlwaysBeExecuted implements ReportPredicate {
    
    public boolean apply(Report report) {
        return true;
    }
}

ShouldBeExecutedOnlyIfPreviousJobHasFinishedWith100PercentSuccess.java

import org.easybatch.core.api.Report;
import org.easybatch.core.api.Status;

public class ShouldBeExecutedOnlyIfPreviousJobHasFinishedWith100PercentSuccess implements ReportPredicate {
    
    public boolean apply(Report report) {
        return Status.FINISHED.equals(report.getStatus()) && report.getSuccessRecordsCount() == report.getTotalRecords();
    }
    
}

ShouldNotBeExecutedIfPreviousHasBeenAborted

import org.easybatch.core.api.Report;
import org.easybatch.core.api.Status;

public class ShouldNotBeExecutedIfPreviousHasBeenAborted implements ReportPredicate {
    
    public boolean apply(Report report) {
        return !Status.ABORTED.equals(report.getStatus());
    }
    
}

Test.java

import org.easybatch.core.api.Engine;
import org.easybatch.core.api.RecordProcessingException;
import org.easybatch.core.api.RecordProcessor;
import org.easybatch.core.impl.EngineBuilder;
import org.easybatch.core.reader.StringRecordReader;
import org.easybatch.core.record.StringRecord;
import org.easyrules.api.RulesEngine;
import org.easyrules.core.RulesEngineBuilder;

public class Test {

    public static void main(String[] args) {
        
        Engine engine1 = EngineBuilder.aNewEngine()
                .named("engine1ThatFinishesWith100percentSuccess")
                .reader(new StringRecordReader("foo\nbar"))
                .processor(new RecordProcessor<StringRecord, StringRecord>() {
                    public StringRecord processRecord(StringRecord record) throws RecordProcessingException {
                        System.out.println("record = " + record);
                        return record;
                    }
                })
                .build();

        Engine engine2 = EngineBuilder.aNewEngine()
                .named("engine2ThatAbortsExecutionOnError")
                .reader(new StringRecordReader("foo\nbar"))
                .processor(new RecordProcessor<StringRecord, StringRecord>() {
                    public StringRecord processRecord(StringRecord record) throws RecordProcessingException {
                        throw new RecordProcessingException("fatal error!");
                    }
                })
                .strictMode(true)
                .build();

        Engine engine3 = EngineBuilder.aNewEngine()
                .named("engine3ThatIsUsedOnlyForTestAndThatWillNotBeCalled")
                .reader(new StringRecordReader("foo"))
                .processor(new RecordProcessor<StringRecord, StringRecord>() {
                    public StringRecord processRecord(StringRecord record) throws RecordProcessingException {
                        System.out.println("engine3 has been called");
                        return record;
                    }
                })
                .build();

        ReportHolder reportHolder = new ReportHolder();
        RulesEngine rulesEngine = RulesEngineBuilder.aNewRulesEngine().build();
        
        JobRule firstJobRule = new JobRule(engine1, reportHolder, new ShouldAlwaysBeExecuted());
        JobRule secondJobRule = new JobRule(engine2, reportHolder, new ShouldBeExecutedOnlyIfPreviousJobHasFinishedWith100PercentSuccess());
        JobRule thirdJobRule = new JobRule(engine3, reportHolder, new ShouldNotBeExecutedIfPreviousHasBeenAborted());
        
        rulesEngine.registerRule(firstJobRule);
        rulesEngine.registerRule(secondJobRule);
        rulesEngine.registerRule(thirdJobRule);
        rulesEngine.fireRules();

    }
}