Groovy setProperty，但有例外

我知道您可以在Groovy类中重写

setProperty

方法来拦截setter逻辑。然而，有时您希望以某种方式截取大多数setter逻辑，但在少数情况下，您希望有一个特殊的逻辑

例如，假设我们有一个如下所示的类：

class PropertyDemo {
    @Override
    void setProperty( String property, Object value ) {
        println "Setting ${property} to ${value.toString()}"
    }

    void setFoo( String whatever ) {
        println 'Foo'
    }

    void setBar( String whatever ) {
        println 'Bar'
    }

    static void main( String[] args ) {
        PropertyDemo demo = new PropertyDemo()
        demo.baz = 'baz'
        demo.foo = 'baz'
        demo.bar = 'baz'
    }
}

Setting baz to baz
Setting foo to baz
Setting bar to baz

main

调用的输出如下：

class PropertyDemo {
    @Override
    void setProperty( String property, Object value ) {
        println "Setting ${property} to ${value.toString()}"
    }

    void setFoo( String whatever ) {
        println 'Foo'
    }

    void setBar( String whatever ) {
        println 'Bar'
    }

    static void main( String[] args ) {
        PropertyDemo demo = new PropertyDemo()
        demo.baz = 'baz'
        demo.foo = 'baz'
        demo.bar = 'baz'
    }
}

Setting baz to baz
Setting foo to baz
Setting bar to baz

如您所见，甚至没有使用特殊的

setFoo

和

setBar

设置器。当然，如果需要，您可以显式地调用它们。您还可以添加以下内容

if( property == 'foo' ) setFoo( value )

在

setProperty

的开头，使用点访问器语法。但我觉得这有点难看。那么，Groovy中是否有现成的支持向

setProperty

添加异常属性，即在上述情况下为

setProperty

和

setBar

创建异常

非常感谢。

以下是更正的代码：

@Override
void setProperty(String property, Object value) {
    def metaProperty = this.metaClass.getMetaProperty(property)
    if(metaProperty) metaProperty.setProperty(this, value)
    else println "Setting ${property} to ${value.toString()}"
}

下面是更正的代码：

@Override
void setProperty(String property, Object value) {
    def metaProperty = this.metaClass.getMetaProperty(property)
    if(metaProperty) metaProperty.setProperty(this, value)
    else println "Setting ${property} to ${value.toString()}"
}

下面是更正的代码：

@Override
void setProperty(String property, Object value) {
    def metaProperty = this.metaClass.getMetaProperty(property)
    if(metaProperty) metaProperty.setProperty(this, value)
    else println "Setting ${property} to ${value.toString()}"
}

下面是更正的代码：

@Override
void setProperty(String property, Object value) {
    def metaProperty = this.metaClass.getMetaProperty(property)
    if(metaProperty) metaProperty.setProperty(this, value)
    else println "Setting ${property} to ${value.toString()}"
}

---

只有当属性丢失时，才能使用

propertyMissing

进行设置：

class PropertyDemo {

  def state

  void propertyMissing( String property, Object value ) {
      state = "Setting ${property} to ${value.toString()}"
  }

  void setFoo( String whatever ) {
      state = 'Foo'
  }

  void setBar( String whatever ) {
      state = 'Bar'
  }
}

def demo = new PropertyDemo()

demo.with {
  baz = 'baz'
  assert state == 'Setting baz to baz'

  foo = 'baz'
  assert state == 'Foo'

  bar = 'baz'
  assert state == 'Bar'
}

---

只有当属性丢失时，才能使用

propertyMissing

进行设置：

class PropertyDemo {

  def state

  void propertyMissing( String property, Object value ) {
      state = "Setting ${property} to ${value.toString()}"
  }

  void setFoo( String whatever ) {
      state = 'Foo'
  }

  void setBar( String whatever ) {
      state = 'Bar'
  }
}

def demo = new PropertyDemo()

demo.with {
  baz = 'baz'
  assert state == 'Setting baz to baz'

  foo = 'baz'
  assert state == 'Foo'

  bar = 'baz'
  assert state == 'Bar'
}

---

只有当属性丢失时，才能使用

propertyMissing

进行设置：

class PropertyDemo {

  def state

  void propertyMissing( String property, Object value ) {
      state = "Setting ${property} to ${value.toString()}"
  }

  void setFoo( String whatever ) {
      state = 'Foo'
  }

  void setBar( String whatever ) {
      state = 'Bar'
  }
}

def demo = new PropertyDemo()

demo.with {
  baz = 'baz'
  assert state == 'Setting baz to baz'

  foo = 'baz'
  assert state == 'Foo'

  bar = 'baz'
  assert state == 'Bar'
}

---

只有当属性丢失时，才能使用

propertyMissing

进行设置：

class PropertyDemo {

  def state

  void propertyMissing( String property, Object value ) {
      state = "Setting ${property} to ${value.toString()}"
  }

  void setFoo( String whatever ) {
      state = 'Foo'
  }

  void setBar( String whatever ) {
      state = 'Bar'
  }
}

def demo = new PropertyDemo()

demo.with {
  baz = 'baz'
  assert state == 'Setting baz to baz'

  foo = 'baz'
  assert state == 'Foo'

  bar = 'baz'
  assert state == 'Bar'
}