Scalar property injection

Injecting scalar properties into a managed node

Introduction

Fluxtion generator will inject scalar properties into the SEP at runtime. The properties are read at generation time and the generated SEP will have the values hard-coded in the generated file. Using property injection client code can inject either default values or constant values into the SEP.

Property type support

The supported types that can be injected into a SEP member are:

• Managed node references

• byte

• char

• short

• int

• float

• long

• double

• String

• Enum

Unsupported types can be written in an @Initialise method, derived from an injected property.

Injection mechanism

The following access patterns for property injection are supported:

Access Pattern	Description
Bean getter/setter	Fluxtion will look for a read/write bean pattern and generate a setXXX call in the SEP
Final fields	A constructor must be available that matches exactly the final fields. If one exists Flxution will generate the constructor call.
public fields	Public fields are values are written in the generated SEP. The field must non-transient, public scope and mutable.

Constructor/field matching will use the logic described here.

Derived final fields are not supported, the class must have a constructor referencing all the final fields.

Example

The example demonstrates all the capabilities of scalar property injection: final fields with constructors, public properties, bean properties and transient properties. The generated SEP contains the values set in the builder.

The example is located here

Node class

public class PropertyHandler {
    //final properties
    private final boolean booleanFinalProp;
//ommitted properties
    private final SampleEnum enumFinalProp;
    //public properties
    public boolean booleanPublicProp;
//ommitted properties
    public SampleEnum enumPublicProp;
    //bean properties
    private boolean booleanBeanProp;
//ommitted properties
    private SampleEnum enumBeanProp;
    //transient properties - ignored
    public transient boolean booleanTransientProp;
//ommitted properties
    public transient SampleEnum enumTransientProp;

    public PropertyHandler(boolean booleanFinalProp, byte byteFinalProp, char charFinalProp, short shortFinalProp, float floatFinalProp, int intFinalProp, double doubleFinalProp, long longFinalProp, String stringFinalProp, SampleEnum enumFinalProp) {
        this.booleanFinalProp = booleanFinalProp;
        this.byteFinalProp = byteFinalProp;
        this.charFinalProp = charFinalProp;
        this.shortFinalProp = shortFinalProp;
        this.floatFinalProp = floatFinalProp;
        this.intFinalProp = intFinalProp;
        this.doubleFinalProp = doubleFinalProp;
        this.longFinalProp = longFinalProp;
        this.stringFinalProp = stringFinalProp;
        this.enumFinalProp = enumFinalProp;
    }

    public boolean isBooleanBeanProp() {
        return booleanBeanProp;
    }

    public void setBooleanBeanProp(boolean booleanBeanProp) {
        this.booleanBeanProp = booleanBeanProp;
    }
    
    public byte getByteBeanProp() {
        return byteBeanProp;
    }

    public void setByteBeanProp(byte byteBeanProp) {
        this.byteBeanProp = byteBeanProp;
    }

    public char getCharBeanProp() {
        return charBeanProp;
    }

    public void setCharBeanProp(char charBeanProp) {
        this.charBeanProp = charBeanProp;
    }

    public short getShortBeanProp() {
        return shortBeanProp;
    }

    public void setShortBeanProp(short shortBeanProp) {
        this.shortBeanProp = shortBeanProp;
    }

    public float getFloatBeanProp() {
        return floatBeanProp;
    }

    public void setFloatBeanProp(float floatBeanProp) {
        this.floatBeanProp = floatBeanProp;
    }

    public int getIntBeanProp() {
        return intBeanProp;
    }

    public void setIntBeanProp(int intBeanProp) {
        this.intBeanProp = intBeanProp;
    }

    public double getDoubleBeanProp() {
        return doubleBeanProp;
    }

    public void setDoubleBeanProp(double doubleBeanProp) {
        this.doubleBeanProp = doubleBeanProp;
    }

    public long getLongBeanProp() {
        return longBeanProp;
    }

    public void setLongBeanProp(long longBeanProp) {
        this.longBeanProp = longBeanProp;
    }

    public String getStringBeanProp() {
        return stringBeanProp;
    }

    public void setStringBeanProp(String stringBeanProp) {
        this.stringBeanProp = stringBeanProp;
    }

    public SampleEnum getEnumBeanProp() {
        return enumBeanProp;
    }

    public void setEnumBeanProp(SampleEnum enumBeanProp) {
        this.enumBeanProp = enumBeanProp;
    }
    
    @EventHandler
    public void myEvent(MyEvent event){
        
    }
    
    @Initialise
    public void init(){
        //calculate and set any derived properties here
    }
}

SEPConfig builder

The builder sets the property values for reading at generation time.

public class Builder extends SEPConfig{

    @Override
    public void buildConfig() {
        PropertyHandler handler = addNode(new PropertyHandler(true, (byte)0,'a',(short)0,0.0f,0,0.0d,0L,"0", MONDAY));
        //boolean
        handler.booleanPublicProp = true;
        handler.booleanTransientProp = true;
        handler.setBooleanBeanProp(true);
        //bytes
        handler.bytePublicProp = (byte)1;
        handler.byteTransientProp = (byte)2;
        handler.setByteBeanProp((byte)3);
        //char
        handler.charPublicProp = 'b';
        handler.charTransientProp = 'c';
        handler.setCharBeanProp('d');
        //short
        handler.shortPublicProp = (short)1;
        handler.shortTransientProp = (short)2;
        handler.setShortBeanProp((short)3);
        //float
        handler.floatPublicProp = (float)1.1;
        handler.floatTransientProp = (float)2.2;
        handler.setFloatBeanProp((float)3.3);
        //int
        handler.intPublicProp = (int)1;
        handler.intTransientProp = (int)2;
        handler.setIntBeanProp((int)3);
        //double
        handler.doublePublicProp = (double)1.1;
        handler.doubleTransientProp = (double)2.2;
        handler.setDoubleBeanProp((double)3.3);
        //long
        handler.longPublicProp = (long)1l;
        handler.longTransientProp = (long)2l;
        handler.setLongBeanProp((long)3l);
        //enum
        handler.enumPublicProp = TUESDAY;
        handler.enumTransientProp = WEDNESDAY;
        handler.setEnumBeanProp(THURSDAY);

    }
    
}

Generated SEP

The generated SEP contains the member values as read at generation time. Complex constructors, bean pattern and public fields are all supported.

Note

• Transient field values are not written in the SEP.

• All values set before constructor exits

public class SampleProcessor implements EventHandler, BatchHandler, Lifecycle {

  //Node declarations
  private final PropertyHandler propertyHandler_1 =
      new PropertyHandler(true, (byte) 0, 'a', (short) 0, 0.0f, 0, 0.0, 0L, "0", SampleEnum.MONDAY);
  //Dirty flags

  //Filter constants

  public SampleProcessor() {
    propertyHandler_1.setBooleanBeanProp(true);
    propertyHandler_1.setByteBeanProp((byte) 3);
    propertyHandler_1.setCharBeanProp('d');
    propertyHandler_1.setDoubleBeanProp(3.3);
    propertyHandler_1.setEnumBeanProp(SampleEnum.THURSDAY);
    propertyHandler_1.setFloatBeanProp(3.3f);
    propertyHandler_1.setIntBeanProp(3);
    propertyHandler_1.setLongBeanProp(3L);
    propertyHandler_1.setShortBeanProp((short) 3);
    propertyHandler_1.booleanPublicProp = (boolean) true;
    propertyHandler_1.bytePublicProp = (byte) 1;
    propertyHandler_1.charPublicProp = 'b';
    propertyHandler_1.shortPublicProp = (short) 1;
    propertyHandler_1.floatPublicProp = (float) 1.1;
    propertyHandler_1.intPublicProp = (int) 1;
    propertyHandler_1.doublePublicProp = (double) 1.1;
    propertyHandler_1.longPublicProp = (long) 1;
    propertyHandler_1.enumPublicProp = com.fluxtion.example.shared.SampleEnum.TUESDAY;
  }

  @Override
  public void onEvent(com.fluxtion.runtime.event.Event event) {
    switch (event.getClass().getName()) {
      case ("com.fluxtion.example.shared.MyEvent"):
        {
          MyEvent typedEvent = (MyEvent) event;
          handleEvent(typedEvent);
          break;
        }
    }
  }

  public void handleEvent(MyEvent typedEvent) {
    //Default, no filter methods
    propertyHandler_1.myEvent(typedEvent);
    //event stack unwind callbacks
    afterEvent();
  }

  @Override
  public void afterEvent() {}

  @Override
  public void init() {
    propertyHandler_1.init();
  }

  @Override
  public void tearDown() {}

  @Override
  public void batchPause() {}

  @Override
  public void batchEnd() {}
}