Promise (Vert.x Stack - Docs 4.5.11 API)

java.lang.Object
- io.vertx.reactivex.core.Promise<T>

Direct Known Subclasses:

ApolloWSConnectionInitEvent, BaseBridgeEvent, ConnectionInitEvent
```
public class Promise<T>
extends Object
```
Represents the writable side of an action that may, or may not, have occurred yet.
The future() method returns the Future associated with a promise, the future can be used for getting notified of the promise completion and retrieve its value.
A promise extends Handler> so it can be used as a callback.
NOTE: This class has been automatically generated from the original non RX-ified interface using Vert.x codegen.

Field Summary

Fields
Modifier and Type Field and Description

static io.vertx.lang.rx.TypeArg<Promise> __TYPE_ARG

io.vertx.lang.rx.TypeArg<T> __typeArg_0

Fields
Modifier and Type	Field and Description
`static io.vertx.lang.rx.TypeArg<Promise>`	`__TYPE_ARG`
`io.vertx.lang.rx.TypeArg<T>`	`__typeArg_0`

Constructor Summary

Constructors
Constructor and Description

Promise(Object delegate, io.vertx.lang.rx.TypeArg<T> typeArg_0)

Promise(Promise delegate)

Constructors
Constructor and Description
`Promise(Object delegate, io.vertx.lang.rx.TypeArg<T> typeArg_0)`
`Promise(Promise delegate)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`complete()` Calls `complete(null)`
`void`	`complete(T result)` Set the result.
`boolean`	`equals(Object o)`
`void`	`fail(String message)` Calls `fail(java.lang.Throwable)` with the `message`.
`void`	`fail(Throwable cause)` Set the failure.
`Future<T>`	`future()`
`Promise`	`getDelegate()`
`int`	`hashCode()`
`static <T> Promise<T>`	`newInstance(Promise arg)`
`static <T> Promise<T>`	`newInstance(Promise arg, io.vertx.lang.rx.TypeArg<T> __typeArg_T)`
`static <T> Promise<T>`	`promise()` Create a promise that hasn't completed yet
`String`	`toString()`
`boolean`	`tryComplete()` Calls `tryComplete(null)`.
`boolean`	`tryComplete(T result)` Like `complete(T)` but returns `false` when the promise is already completed instead of throwing an `IllegalStateException`, it returns `true` otherwise.
`boolean`	`tryFail(String message)` Calls `fail(java.lang.Throwable)` with the `message`.
`boolean`	`tryFail(Throwable cause)` Like `fail(java.lang.Throwable)` but returns `false` when the promise is already completed instead of throwing an `IllegalStateException`, it returns `true` otherwise.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Field Detail
  - __TYPE_ARG
```
public static final io.vertx.lang.rx.TypeArg<Promise> __TYPE_ARG
```
  - __typeArg_0
```
public final io.vertx.lang.rx.TypeArg<T> __typeArg_0
```
- Constructor Detail
  - Promise
```
public Promise(Promise delegate)
```
  - Promise
```
public Promise(Object delegate,
               io.vertx.lang.rx.TypeArg<T> typeArg_0)
```
- Method Detail
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - equals
```
public boolean equals(Object o)
```
    Overrides:
    
    equals in class Object
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - getDelegate
```
public Promise getDelegate()
```
  - promise
```
public static <T> Promise<T> promise()
```
    Create a promise that hasn't completed yet
    
    Returns:
    
    the promise
  - complete
```
public void complete(T result)
```
    Set the result. Any handler will be called, if there is one, and the promise will be marked as completed.
    Any handler set on the associated promise will be called.
    
    Parameters:
    
    result - the result
  - complete
```
public void complete()
```
    Calls complete(null)
  - fail
```
public void fail(Throwable cause)
```
    Set the failure. Any handler will be called, if there is one, and the future will be marked as completed.
    
    Parameters:
    
    cause - the failure cause
  - fail
```
public void fail(String message)
```
    Calls fail(java.lang.Throwable) with the message.
    
    Parameters:
    
    message - the failure message
  - tryComplete
```
public boolean tryComplete(T result)
```
    Like complete(T) but returns false when the promise is already completed instead of throwing an IllegalStateException, it returns true otherwise.
    
    Parameters:
    
    result - the result
    
    Returns:
    
    false when the future is already completed
  - tryComplete
```
public boolean tryComplete()
```
    Calls tryComplete(null).
    
    Returns:
    
    false when the future is already completed
  - tryFail
```
public boolean tryFail(Throwable cause)
```
    Like fail(java.lang.Throwable) but returns false when the promise is already completed instead of throwing an IllegalStateException, it returns true otherwise.
    
    Parameters:
    
    cause - the failure cause
    
    Returns:
    
    false when the future is already completed
  - tryFail
```
public boolean tryFail(String message)
```
    Calls fail(java.lang.Throwable) with the message.
    
    Parameters:
    
    message - the failure message
    
    Returns:
    
    false when the future is already completed
  - future
```
public Future<T> future()
```
    Returns:
    
    the Future associated with this promise, it can be used to be aware of the promise completion
  - newInstance
```
public static <T> Promise<T> newInstance(Promise arg)
```
  - newInstance
```
public static <T> Promise<T> newInstance(Promise arg,
                                         io.vertx.lang.rx.TypeArg<T> __typeArg_T)
```

Class Promise<T>

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

__TYPE_ARG

__typeArg_0

Constructor Detail

Promise

Promise

Method Detail

toString

equals

hashCode

getDelegate

promise

complete

complete

fail

fail

tryComplete

tryComplete

tryFail

tryFail

future

newInstance

newInstance