Java 8 brings power to testing!

Java 8 without a doubt is most revolutionary release of last years. Many mechanisms and techniques, recently available only in languages like Groovy or Scala are now used by Java developers on a daily basis. However in order to benefit from them, sometimes it is required to radically change a mindset.

During my presentation I will show some tricks and examples how to take advantage of Java 8 in implementing more consistent and readable tests and how to rewrite existing testing tools to benefit even more.

Transcript

1. Java 8 brings power to testing!
   Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
   Poznań, 30th January 2015
   

   View Slide

2. 3 interesting companies
   Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
   

   View Slide

3. Java 8
   The most revolutionary Java version released in recent
   years
   Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
   

   View Slide

4. Java 8
   The most revolutionary Java version released in recent
   years
   Focus on lambda expressions and method references
   Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
   

   View Slide

5. Java 8
   The most revolutionary Java version released in recent
   years
   Focus on lambda expressions and method references
   Constructions known from Groovy or Scala become
   available (even if they look uglier)
   Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
   

   View Slide

6. Java 8
   The most revolutionary Java version released in recent
   years
   Focus on lambda expressions and method references
   Constructions known from Groovy or Scala become
   available (even if they look uglier)
   How can it improve our testing code and testing tools?
   Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
   

   View Slide

7. Case study 1:
   AssertJ
   Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
   

   View Slide

8. AssertJ - Fluent assertions for Java
   Continuation of FEST-Assert
   Large set of strongly typed assertions
   a
   s
   s
   e
   r
   t
   T
   h
   a
   t
   (
   d
   a
   t
   e
   T
   o
   A
   s
   s
   e
   r
   t
   ) /
   /
   D
   a
   t
   e
   .
   i
   s
   A
   f
   t
   e
   r
   (
   d
   a
   t
   e
   1
   )
   .
   i
   s
   N
   o
   t
   B
   e
   t
   w
   e
   e
   n
   (
   d
   a
   t
   e
   2
   , d
   a
   t
   e
   3
   )
   ;
   a
   s
   s
   e
   r
   t
   T
   h
   a
   t
   (
   l
   i
   s
   t
   T
   o
   A
   s
   s
   e
   r
   t
   ) /
   /
   L
   i
   s
   t
   , S
   e
   t
   , m
   a
   j
   o
   r
   i
   t
   y a
   l
   s
   o f
   o
   r I
   t
   e
   r
   a
   b
   l
   e
   .
   h
   a
   s
   S
   i
   z
   e
   (
   5
   )
   .
   c
   o
   n
   t
   a
   i
   n
   s
   (
   "
   F
   o
   o
   "
   , "
   B
   a
   r
   "
   )
   .
   d
   o
   e
   s
   N
   o
   t
   C
   o
   n
   t
   a
   i
   n
   (
   "
   X
   X
   X
   "
   )
   ;
   a
   s
   s
   e
   r
   t
   T
   h
   a
   t
   (
   m
   a
   p
   T
   o
   A
   s
   s
   e
   r
   t
   ) /
   /
   M
   a
   p
   .
   h
   a
   s
   S
   i
   z
   e
   (
   7
   )
   .
   c
   o
   n
   t
   a
   i
   n
   s
   K
   e
   y
   (
   4
   2
   )
   .
   c
   o
   n
   t
   a
   i
   n
   s
   E
   n
   t
   r
   y
   (
   1
   3
   , "
   F
   r
   i
   d
   a
   y
   "
   )
   .
   d
   o
   e
   s
   N
   o
   t
   C
   o
   n
   t
   a
   i
   n
   V
   a
   l
   u
   e
   (
   "
   F
   r
   e
   d
   d
   y
   "
   )
   ;
   Additional modules for Guava, Joda-Time, Neo4j and
   Android
   Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
   

   View Slide

9. AssertJ - Java 8 edition
   A completely separate branch
   New method signatures
   New classes
   Support for new features
   j
   a
   v
   a
   .
   u
   t
   i
   l
   .
   O
   p
   t
   i
   o
   n
   a
   l
   Date and Time API (JSR 310)
   Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
   

   View Slide

10. Manual fields extraction (antipattern)
    c
    l
    a
    s
    s F
    e
    l
    l
    o
    w {
    p
    r
    i
    v
    a
    t
    e f
    i
    n
    a
    l S
    t
    r
    i
    n
    g n
    a
    m
    e
    ;
    p
    r
    i
    v
    a
    t
    e f
    i
    n
    a
    l R
    a
    c
    e r
    a
    c
    e
    ;
    (
    .
    .
    .
    )
    }
    c
    l
    a
    s
    s F
    e
    l
    l
    o
    w
    s
    h
    i
    p i
    m
    p
    l
    e
    m
    e
    n
    t
    s I
    t
    e
    r
    a
    b
    l
    e
    <
    F
    e
    l
    l
    o
    w
    > {
    p
    r
    i
    v
    a
    t
    e f
    i
    n
    a
    l L
    i
    s
    t
    <
    F
    e
    l
    l
    o
    w
    > f
    e
    l
    l
    o
    w
    s
    ;
    (
    .
    .
    .
    )
    }
    @
    T
    e
    s
    t
    p
    u
    b
    l
    i
    c v
    o
    i
    d s
    h
    o
    u
    l
    d
    D
    o
    M
    a
    n
    u
    a
    l
    E
    x
    t
    r
    a
    c
    t
    i
    o
    n
    I
    n
    J
    a
    v
    a
    7
    (
    ) { /
    /
    d
    o
    n
    '
    t d
    o t
    h
    a
    t
    L
    i
    s
    t
    <
    S
    t
    r
    i
    n
    g
    > n
    a
    m
    e
    s = n
    e
    w A
    r
    r
    a
    y
    L
    i
    s
    t
    <
    >
    (
    )
    ;
    f
    o
    r (
    F
    e
    l
    l
    o
    w f
    e
    l
    l
    o
    w : f
    e
    l
    l
    o
    w
    s
    h
    i
    p
    ) {
    n
    a
    m
    e
    s
    .
    a
    d
    d
    (
    f
    e
    l
    l
    o
    w
    .
    g
    e
    t
    N
    a
    m
    e
    (
    )
    )
    ;
    }
    a
    s
    s
    e
    r
    t
    T
    h
    a
    t
    (
    n
    a
    m
    e
    s
    )
    .
    c
    o
    n
    t
    a
    i
    n
    s
    (
    "
    G
    a
    n
    d
    a
    l
    f
    "
    , "
    L
    e
    g
    o
    l
    a
    s
    "
    )
    .
    d
    o
    e
    s
    N
    o
    t
    C
    o
    n
    t
    a
    i
    n
    (
    "
    S
    a
    u
    r
    o
    n
    "
    )
    ;
    }
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

11. AssertJ - fields extraction
    c
    l
    a
    s
    s F
    e
    l
    l
    o
    w {
    p
    r
    i
    v
    a
    t
    e f
    i
    n
    a
    l S
    t
    r
    i
    n
    g n
    a
    m
    e
    ;
    p
    r
    i
    v
    a
    t
    e f
    i
    n
    a
    l R
    a
    c
    e r
    a
    c
    e
    ;
    (
    .
    .
    .
    )
    }
    c
    l
    a
    s
    s F
    e
    l
    l
    o
    w
    s
    h
    i
    p i
    m
    p
    l
    e
    m
    e
    n
    t
    s I
    t
    e
    r
    a
    b
    l
    e
    <
    F
    e
    l
    l
    o
    w
    > {
    p
    r
    i
    v
    a
    t
    e f
    i
    n
    a
    l L
    i
    s
    t
    <
    F
    e
    l
    l
    o
    w
    > f
    e
    l
    l
    o
    w
    s
    ;
    (
    .
    .
    .
    )
    }
    @
    T
    e
    s
    t
    p
    u
    b
    l
    i
    c v
    o
    i
    d s
    h
    o
    u
    l
    d
    E
    x
    t
    r
    a
    c
    t
    F
    i
    e
    l
    d
    I
    n
    J
    a
    v
    a
    7
    (
    ) {
    a
    s
    s
    e
    r
    t
    T
    h
    a
    t
    (
    f
    e
    l
    l
    o
    w
    s
    h
    i
    p
    )
    .
    e
    x
    t
    r
    a
    c
    t
    i
    n
    g
    (
    "
    n
    a
    m
    e
    "
    )
    .
    c
    o
    n
    t
    a
    i
    n
    s
    (
    "
    G
    a
    n
    d
    a
    l
    f
    "
    , "
    L
    e
    g
    o
    l
    a
    s
    "
    ) /
    /
    O
    b
    j
    e
    c
    t
    .
    d
    o
    e
    s
    N
    o
    t
    C
    o
    n
    t
    a
    i
    n
    (
    "
    S
    a
    u
    r
    o
    n
    "
    )
    ; /
    /
    O
    b
    j
    e
    c
    t
    }
    Field name as String - error-prone and hard to refactor
    No strong typing
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

12. AssertJ - fields extraction - Java 8
    @
    T
    e
    s
    t
    p
    u
    b
    l
    i
    c v
    o
    i
    d s
    h
    o
    u
    l
    d
    E
    x
    t
    r
    a
    c
    t
    F
    i
    e
    l
    d
    W
    i
    t
    h
    M
    e
    t
    h
    o
    d
    R
    e
    f
    e
    r
    e
    n
    c
    e
    (
    ) {
    a
    s
    s
    e
    r
    t
    T
    h
    a
    t
    (
    f
    e
    l
    l
    o
    w
    s
    h
    i
    p
    )
    .
    e
    x
    t
    r
    a
    c
    t
    i
    n
    g
    (
    F
    e
    l
    l
    o
    w
    :
    :
    g
    e
    t
    N
    a
    m
    e
    )
    .
    c
    o
    n
    t
    a
    i
    n
    s
    (
    "
    G
    a
    n
    d
    a
    l
    f
    "
    , "
    L
    e
    g
    o
    l
    a
    s
    "
    ) /
    /
    S
    t
    r
    i
    n
    g
    .
    d
    o
    e
    s
    N
    o
    t
    C
    o
    n
    t
    a
    i
    n
    (
    "
    S
    a
    u
    r
    o
    n
    "
    )
    ; /
    /
    S
    t
    r
    i
    n
    g
    }
    Method reference - safer, easy to refactor
    Strong typing
    Preview in assertj-core-java8 1.0.0m1
    Will be available in AssertJ 2.0
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

13. Manual fields extraction - Java 8
    (antipattern)
    Why not pure Java 8 Streams?
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

14. Manual fields extraction - Java 8
    (antipattern)
    Why not pure Java 8 Streams?
    @
    T
    e
    s
    t
    p
    u
    b
    l
    i
    c v
    o
    i
    d s
    h
    o
    u
    l
    d
    D
    o
    M
    a
    n
    u
    a
    l
    E
    x
    t
    r
    a
    c
    t
    i
    o
    n
    I
    n
    J
    a
    v
    a
    8
    (
    ) { /
    /
    d
    o
    n
    '
    t d
    o t
    h
    a
    t
    L
    i
    s
    t
    <
    S
    t
    r
    i
    n
    g
    > n
    a
    m
    e
    s = S
    t
    r
    e
    a
    m
    S
    u
    p
    p
    o
    r
    t
    .
    s
    t
    r
    e
    a
    m
    (
    f
    e
    l
    l
    o
    w
    s
    h
    i
    p
    .
    s
    p
    l
    i
    t
    e
    r
    a
    t
    o
    r
    (
    )
    ,
    .
    m
    a
    p
    (
    F
    e
    l
    l
    o
    w
    :
    :
    g
    e
    t
    N
    a
    m
    e
    )
    .
    c
    o
    l
    l
    e
    c
    t
    (
    C
    o
    l
    l
    e
    c
    t
    o
    r
    s
    .
    t
    o
    L
    i
    s
    t
    (
    )
    )
    ;
    a
    s
    s
    e
    r
    t
    T
    h
    a
    t
    (
    n
    a
    m
    e
    s
    )
    .
    c
    o
    n
    t
    a
    i
    n
    s
    (
    "
    G
    a
    n
    d
    a
    l
    f
    "
    , "
    L
    e
    g
    o
    l
    a
    s
    "
    )
    .
    d
    o
    e
    s
    N
    o
    t
    C
    o
    n
    t
    a
    i
    n
    (
    "
    S
    a
    u
    r
    o
    n
    "
    )
    ;
    }
    Functional, but still bloated
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

15. Case study 2:
    Awaitility
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

16. Awaitility
    Smart asynchronous call testing
    Adaptable waiting for completion
    Finishes as quickly as condition is fulfilled
    No more s
    l
    e
    e
    p
    (
    5
    0
    0
    0
    ) in tests
    Separate support for Groovy and Scala traits and closures
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

17. Awaitility
    Communication with queue
    p
    u
    b
    l
    i
    c i
    n
    t
    e
    r
    f
    a
    c
    e M
    e
    s
    s
    a
    g
    e
    Q
    u
    e
    u
    e
    F
    a
    c
    a
    d
    e {
    v
    o
    i
    d s
    e
    n
    d
    P
    i
    n
    g
    (
    )
    ;
    i
    n
    t g
    e
    t
    N
    u
    m
    b
    e
    r
    O
    f
    R
    e
    c
    e
    i
    v
    e
    d
    P
    a
    c
    k
    e
    t
    s
    (
    )
    ;
    }
    @
    T
    e
    s
    t
    p
    u
    b
    l
    i
    c v
    o
    i
    d r
    e
    s
    p
    o
    n
    s
    e
    S
    h
    o
    u
    l
    d
    B
    e
    A
    v
    a
    i
    l
    a
    b
    l
    e
    A
    f
    t
    e
    r
    S
    o
    m
    e
    T
    i
    m
    e
    P
    r
    o
    x
    y
    E
    d
    i
    t
    i
    o
    n
    (
    ) {
    /
    /
    w
    h
    e
    n
    q
    u
    e
    u
    e
    F
    a
    c
    a
    d
    e
    .
    s
    e
    n
    d
    P
    i
    n
    g
    (
    )
    ;
    /
    /
    t
    h
    e
    n
    a
    w
    a
    i
    t
    (
    )
    .
    u
    n
    t
    i
    l
    C
    a
    l
    l
    (
    t
    o
    (
    q
    u
    e
    u
    e
    F
    a
    c
    a
    d
    e
    )
    .
    g
    e
    t
    N
    u
    m
    b
    e
    r
    O
    f
    R
    e
    c
    e
    i
    v
    e
    d
    P
    a
    c
    k
    e
    t
    s
    (
    )
    , e
    q
    u
    a
    l
    T
    o
    (
    1
    )
    )
    }
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

18. Awaitility
    Assertions & matchers
    Clear and verbose error message:
    C
    o
    n
    d
    i
    t
    i
    o
    n
    T
    i
    m
    e
    o
    u
    t
    E
    x
    c
    e
    p
    t
    i
    o
    n
    : M
    e
    s
    s
    a
    g
    e
    Q
    u
    e
    u
    e
    F
    a
    c
    a
    d
    e
    .
    g
    e
    t
    N
    u
    m
    b
    e
    r
    O
    f
    R
    e
    c
    e
    i
    v
    e
    d
    P
    a
    c
    k
    e
    t
    s
    (
    )
    e
    x
    p
    e
    c
    t
    e
    d <
    1
    > b
    u
    t w
    a
    s <
    0
    > w
    i
    t
    h
    i
    n 5 s
    e
    c
    o
    n
    d
    s
    .
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

19. Awaitility
    Assertions & matchers
    Clear and verbose error message:
    C
    o
    n
    d
    i
    t
    i
    o
    n
    T
    i
    m
    e
    o
    u
    t
    E
    x
    c
    e
    p
    t
    i
    o
    n
    : M
    e
    s
    s
    a
    g
    e
    Q
    u
    e
    u
    e
    F
    a
    c
    a
    d
    e
    .
    g
    e
    t
    N
    u
    m
    b
    e
    r
    O
    f
    R
    e
    c
    e
    i
    v
    e
    d
    P
    a
    c
    k
    e
    t
    s
    (
    )
    e
    x
    p
    e
    c
    t
    e
    d <
    1
    > b
    u
    t w
    a
    s <
    0
    > w
    i
    t
    h
    i
    n 5 s
    e
    c
    o
    n
    d
    s
    .
    Drawbacks
    Not so easy with complicated matching expression
    I personally prefer AssertJ over Hamcrest
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

20. Awaitility with Java 8
    Java 7:
    @
    T
    e
    s
    t
    p
    u
    b
    l
    i
    c v
    o
    i
    d r
    e
    s
    p
    o
    n
    s
    e
    S
    h
    o
    u
    l
    d
    B
    e
    A
    v
    a
    i
    l
    a
    b
    l
    e
    A
    f
    t
    e
    r
    S
    o
    m
    e
    T
    i
    m
    e
    (
    ) {
    /
    /
    w
    h
    e
    n
    q
    u
    e
    u
    e
    F
    a
    c
    a
    d
    e
    .
    s
    e
    n
    d
    P
    i
    n
    g
    (
    )
    ;
    /
    /
    t
    h
    e
    n
    a
    w
    a
    i
    t
    (
    )
    .
    u
    n
    t
    i
    l
    (
    g
    e
    t
    N
    u
    m
    b
    e
    r
    O
    f
    R
    e
    c
    e
    i
    v
    e
    d
    P
    a
    c
    k
    e
    t
    s
    (
    )
    , e
    q
    u
    a
    l
    T
    o
    (
    1
    )
    )
    ;
    }
    p
    r
    i
    v
    a
    t
    e C
    a
    l
    l
    a
    b
    l
    e
    <
    I
    n
    t
    e
    g
    e
    r
    > g
    e
    t
    N
    u
    m
    b
    e
    r
    O
    f
    R
    e
    c
    e
    i
    v
    e
    d
    P
    a
    c
    k
    e
    t
    s
    (
    ) {
    r
    e
    t
    u
    r
    n n
    e
    w C
    a
    l
    l
    a
    b
    l
    e
    <
    I
    n
    t
    e
    g
    e
    r
    >
    (
    ) {
    p
    u
    b
    l
    i
    c I
    n
    t
    e
    g
    e
    r c
    a
    l
    l
    (
    ) t
    h
    r
    o
    w
    s E
    x
    c
    e
    p
    t
    i
    o
    n {
    r
    e
    t
    u
    r
    n q
    u
    e
    u
    e
    F
    a
    c
    a
    d
    e
    .
    g
    e
    t
    N
    u
    m
    b
    e
    r
    O
    f
    R
    e
    c
    e
    i
    v
    e
    d
    P
    a
    c
    k
    e
    t
    s
    (
    )
    ;
    }
    }
    ;
    }
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

21. Awaitility with Java 8
    Java 8 - lambda expression
    @
    T
    e
    s
    t
    p
    u
    b
    l
    i
    c v
    o
    i
    d r
    e
    s
    p
    o
    n
    s
    e
    S
    h
    o
    u
    l
    d
    B
    e
    A
    v
    a
    i
    l
    a
    b
    l
    e
    A
    f
    t
    e
    r
    S
    o
    m
    e
    T
    i
    m
    e
    8
    (
    ) {
    /
    /
    w
    h
    e
    n
    q
    u
    e
    u
    e
    F
    a
    c
    a
    d
    e
    .
    s
    e
    n
    d
    P
    i
    n
    g
    (
    )
    ;
    /
    /
    t
    h
    e
    n
    a
    w
    a
    i
    t
    (
    )
    .
    u
    n
    t
    i
    l
    (
    (
    ) -
    > q
    u
    e
    u
    e
    F
    a
    c
    a
    d
    e
    .
    g
    e
    t
    N
    u
    m
    b
    e
    r
    O
    f
    R
    e
    c
    e
    i
    v
    e
    d
    P
    a
    c
    k
    e
    t
    s
    (
    )
    , e
    q
    u
    a
    l
    T
    o
    (
    1
    )
    )
    ;
    }
    Java 8 - method reference
    a
    w
    a
    i
    t
    (
    )
    .
    u
    n
    t
    i
    l
    (
    q
    u
    e
    u
    e
    F
    a
    c
    a
    d
    e
    :
    :
    g
    e
    t
    N
    u
    m
    b
    e
    r
    O
    f
    R
    e
    c
    e
    i
    v
    e
    d
    P
    a
    c
    k
    e
    t
    s
    , e
    q
    u
    a
    l
    T
    o
    (
    1
    )
    )
    ;
    Question - do I need Hamcrest in Java 8 world?
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

22. Awaitility with Java 8 without Hamcrest
    @
    T
    e
    s
    t
    p
    u
    b
    l
    i
    c v
    o
    i
    d r
    e
    s
    p
    o
    n
    s
    e
    S
    h
    o
    u
    l
    d
    B
    e
    A
    v
    a
    i
    l
    a
    b
    l
    e
    A
    f
    t
    e
    r
    S
    o
    m
    e
    T
    i
    m
    e
    J
    a
    v
    a
    8
    E
    d
    i
    t
    i
    o
    n
    (
    ) {
    /
    /
    w
    h
    e
    n
    q
    u
    e
    u
    e
    F
    a
    c
    a
    d
    e
    .
    s
    e
    n
    d
    P
    i
    n
    g
    (
    )
    ;
    /
    /
    t
    h
    e
    n
    a
    w
    a
    i
    t
    (
    )
    .
    u
    n
    t
    i
    l
    (
    (
    ) -
    > q
    u
    e
    u
    e
    F
    a
    c
    a
    d
    e
    .
    g
    e
    t
    N
    u
    m
    b
    e
    r
    O
    f
    R
    e
    c
    e
    i
    v
    e
    d
    P
    a
    c
    k
    e
    t
    s
    (
    ) =
    = 1
    )
    ;
    }
    Clear and verbose error message?
    C
    o
    n
    d
    i
    t
    i
    o
    n
    T
    i
    m
    e
    o
    u
    t
    E
    x
    c
    e
    p
    t
    i
    o
    n
    : D
    e
    l
    a
    y
    e
    d
    D
    e
    l
    i
    v
    e
    r
    y
    M
    Q
    F
    a
    c
    a
    d
    e
    .
    g
    e
    t
    N
    u
    m
    b
    e
    r
    O
    f
    R
    e
    c
    e
    i
    v
    e
    d
    P
    a
    c
    k
    e
    t
    s
    (
    )
    e
    x
    p
    e
    c
    t
    e
    d <
    1
    > b
    u
    t w
    a
    s <
    0
    > w
    i
    t
    h
    i
    n 5 s
    e
    c
    o
    n
    d
    s
    .
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

23. Awaitility with Java 8 without Hamcrest
    @
    T
    e
    s
    t
    p
    u
    b
    l
    i
    c v
    o
    i
    d r
    e
    s
    p
    o
    n
    s
    e
    S
    h
    o
    u
    l
    d
    B
    e
    A
    v
    a
    i
    l
    a
    b
    l
    e
    A
    f
    t
    e
    r
    S
    o
    m
    e
    T
    i
    m
    e
    J
    a
    v
    a
    8
    E
    d
    i
    t
    i
    o
    n
    (
    ) {
    /
    /
    w
    h
    e
    n
    q
    u
    e
    u
    e
    F
    a
    c
    a
    d
    e
    .
    s
    e
    n
    d
    P
    i
    n
    g
    (
    )
    ;
    /
    /
    t
    h
    e
    n
    a
    w
    a
    i
    t
    (
    )
    .
    u
    n
    t
    i
    l
    (
    (
    ) -
    > q
    u
    e
    u
    e
    F
    a
    c
    a
    d
    e
    .
    g
    e
    t
    N
    u
    m
    b
    e
    r
    O
    f
    R
    e
    c
    e
    i
    v
    e
    d
    P
    a
    c
    k
    e
    t
    s
    (
    ) =
    = 1
    )
    ;
    }
    Clear and verbose error message?
    C
    o
    n
    d
    i
    t
    i
    o
    n
    T
    i
    m
    e
    o
    u
    t
    E
    x
    c
    e
    p
    t
    i
    o
    n
    : D
    e
    l
    a
    y
    e
    d
    D
    e
    l
    i
    v
    e
    r
    y
    M
    Q
    F
    a
    c
    a
    d
    e
    .
    g
    e
    t
    N
    u
    m
    b
    e
    r
    O
    f
    R
    e
    c
    e
    i
    v
    e
    d
    P
    a
    c
    k
    e
    t
    s
    (
    )
    e
    x
    p
    e
    c
    t
    e
    d <
    1
    > b
    u
    t w
    a
    s <
    0
    > w
    i
    t
    h
    i
    n 5 s
    e
    c
    o
    n
    d
    s
    .
    Not anymore
    C
    o
    n
    d
    i
    t
    i
    o
    n
    T
    i
    m
    e
    o
    u
    t
    E
    x
    c
    e
    p
    t
    i
    o
    n
    : C
    o
    n
    d
    i
    t
    i
    o
    n w
    i
    t
    h l
    a
    m
    b
    d
    a e
    x
    p
    r
    e
    s
    s
    i
    o
    n i
    n
    A
    w
    a
    i
    t
    i
    l
    i
    t
    y
    A
    s
    y
    n
    c
    h
    T
    e
    s
    t w
    a
    s n
    o
    t f
    u
    l
    f
    i
    l
    l
    e
    d w
    i
    t
    h
    i
    n 5 s
    e
    c
    o
    n
    d
    s
    .
    Expected 1, but was 0? 2? 3? -1?
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

24. Awaitility and AssertJ
    @
    T
    e
    s
    t
    p
    u
    b
    l
    i
    c v
    o
    i
    d r
    e
    s
    p
    o
    n
    s
    e
    S
    h
    o
    u
    l
    d
    B
    e
    A
    v
    a
    i
    l
    a
    b
    l
    e
    A
    f
    t
    e
    r
    S
    o
    m
    e
    T
    i
    m
    e
    J
    a
    v
    a
    8
    E
    d
    i
    t
    i
    o
    n
    2
    (
    ) {
    /
    /
    w
    h
    e
    n
    q
    u
    e
    u
    e
    F
    a
    c
    a
    d
    e
    .
    s
    e
    n
    d
    P
    i
    n
    g
    (
    )
    ;
    /
    /
    t
    h
    e
    n
    a
    w
    a
    i
    t
    (
    )
    .
    u
    n
    t
    i
    l
    (
    (
    ) -
    >
    a
    s
    s
    e
    r
    t
    T
    h
    a
    t
    (
    q
    u
    e
    u
    e
    F
    a
    c
    a
    d
    e
    .
    g
    e
    t
    N
    u
    m
    b
    e
    r
    O
    f
    R
    e
    c
    e
    i
    v
    e
    d
    P
    a
    c
    k
    e
    t
    s
    (
    )
    )
    .
    i
    s
    E
    q
    u
    a
    l
    T
    o
    (
    1
    )
    )
    ;
    }
    Still clear and verbose error message from AssertJ:
    C
    o
    n
    d
    i
    t
    i
    o
    n
    T
    i
    m
    e
    o
    u
    t
    E
    x
    c
    e
    p
    t
    i
    o
    n
    : C
    o
    n
    d
    i
    t
    i
    o
    n d
    e
    f
    i
    n
    e
    d a
    s a l
    a
    m
    b
    d
    a e
    x
    p
    r
    e
    s
    s
    i
    o
    n
    i
    n A
    w
    a
    i
    t
    i
    l
    i
    t
    y
    A
    s
    y
    n
    c
    h
    T
    e
    s
    t e
    x
    p
    e
    c
    t
    e
    d
    :
    <
    [
    1
    ]
    > b
    u
    t w
    a
    s
    :
    <
    [
    0
    ]
    > w
    i
    t
    h
    i
    n 5 s
    e
    c
    o
    n
    d
    s
    .
    Would it possible?
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

25. Awaitility and AssertJ - Internals
    One evening of hacking
    p
    u
    b
    l
    i
    c A
    s
    s
    e
    r
    t
    i
    o
    n
    C
    o
    n
    d
    i
    t
    i
    o
    n
    (
    f
    i
    n
    a
    l R
    u
    n
    n
    a
    b
    l
    e s
    u
    p
    p
    l
    i
    e
    r
    , C
    o
    n
    d
    i
    t
    i
    o
    n
    S
    e
    t
    t
    i
    n
    g
    s s
    e
    t
    t
    i
    n
    g
    s
    )
    i
    f (
    s
    u
    p
    p
    l
    i
    e
    r =
    = n
    u
    l
    l
    ) { t
    h
    r
    o
    w n
    e
    w I
    l
    l
    e
    g
    a
    l
    A
    r
    g
    u
    m
    e
    n
    t
    E
    x
    c
    e
    p
    t
    i
    o
    n
    (
    "
    .
    .
    .
    "
    )
    ; }
    C
    a
    l
    l
    a
    b
    l
    e
    <
    B
    o
    o
    l
    e
    a
    n
    > c
    a
    l
    l
    a
    b
    l
    e = n
    e
    w C
    a
    l
    l
    a
    b
    l
    e
    <
    B
    o
    o
    l
    e
    a
    n
    >
    (
    ) {
    p
    u
    b
    l
    i
    c B
    o
    o
    l
    e
    a
    n c
    a
    l
    l
    (
    ) t
    h
    r
    o
    w
    s E
    x
    c
    e
    p
    t
    i
    o
    n {
    t
    r
    y {
    s
    u
    p
    p
    l
    i
    e
    r
    .
    r
    u
    n
    (
    )
    ;
    r
    e
    t
    u
    r
    n t
    r
    u
    e
    ;
    } c
    a
    t
    c
    h (
    A
    s
    s
    e
    r
    t
    i
    o
    n
    E
    r
    r
    o
    r e
    ) {
    l
    a
    s
    t
    E
    x
    c
    e
    p
    t
    i
    o
    n
    M
    e
    s
    s
    a
    g
    e = e
    .
    g
    e
    t
    M
    e
    s
    s
    a
    g
    e
    (
    )
    ;
    r
    e
    t
    u
    r
    n f
    a
    l
    s
    e
    ;
    }
    }
    }
    ;
    c
    o
    n
    d
    i
    t
    i
    o
    n
    A
    w
    a
    i
    t
    e
    r = n
    e
    w C
    o
    n
    d
    i
    t
    i
    o
    n
    A
    w
    a
    i
    t
    e
    r
    (
    c
    a
    l
    l
    a
    b
    l
    e
    , s
    e
    t
    t
    i
    n
    g
    s
    ) {
    @
    O
    v
    e
    r
    r
    i
    d
    e
    p
    r
    o
    t
    e
    c
    t
    e
    d S
    t
    r
    i
    n
    g g
    e
    t
    T
    i
    m
    e
    o
    u
    t
    M
    e
    s
    s
    a
    g
    e
    (
    ) {
    r
    e
    t
    u
    r
    n s
    u
    p
    p
    l
    i
    e
    r
    .
    g
    e
    t
    C
    l
    a
    s
    s
    (
    )
    .
    g
    e
    t
    N
    a
    m
    e
    (
    ) + " " + l
    a
    s
    t
    E
    x
    c
    e
    p
    t
    i
    o
    n
    M
    e
    s
    s
    a
    g
    e
    ;
    }
    }
    ;
    }
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

26. Awaitility and AssertJ - Internals
    One evening of hacking
    p
    u
    b
    l
    i
    c A
    s
    s
    e
    r
    t
    i
    o
    n
    C
    o
    n
    d
    i
    t
    i
    o
    n
    (
    f
    i
    n
    a
    l R
    u
    n
    n
    a
    b
    l
    e s
    u
    p
    p
    l
    i
    e
    r
    , C
    o
    n
    d
    i
    t
    i
    o
    n
    S
    e
    t
    t
    i
    n
    g
    s s
    e
    t
    t
    i
    n
    g
    s
    )
    i
    f (
    s
    u
    p
    p
    l
    i
    e
    r =
    = n
    u
    l
    l
    ) { t
    h
    r
    o
    w n
    e
    w I
    l
    l
    e
    g
    a
    l
    A
    r
    g
    u
    m
    e
    n
    t
    E
    x
    c
    e
    p
    t
    i
    o
    n
    (
    "
    .
    .
    .
    "
    )
    ; }
    C
    a
    l
    l
    a
    b
    l
    e
    <
    B
    o
    o
    l
    e
    a
    n
    > c
    a
    l
    l
    a
    b
    l
    e = n
    e
    w C
    a
    l
    l
    a
    b
    l
    e
    <
    B
    o
    o
    l
    e
    a
    n
    >
    (
    ) {
    p
    u
    b
    l
    i
    c B
    o
    o
    l
    e
    a
    n c
    a
    l
    l
    (
    ) t
    h
    r
    o
    w
    s E
    x
    c
    e
    p
    t
    i
    o
    n {
    t
    r
    y {
    s
    u
    p
    p
    l
    i
    e
    r
    .
    r
    u
    n
    (
    )
    ;
    r
    e
    t
    u
    r
    n t
    r
    u
    e
    ;
    } c
    a
    t
    c
    h (
    A
    s
    s
    e
    r
    t
    i
    o
    n
    E
    r
    r
    o
    r e
    ) {
    l
    a
    s
    t
    E
    x
    c
    e
    p
    t
    i
    o
    n
    M
    e
    s
    s
    a
    g
    e = e
    .
    g
    e
    t
    M
    e
    s
    s
    a
    g
    e
    (
    )
    ;
    r
    e
    t
    u
    r
    n f
    a
    l
    s
    e
    ;
    }
    }
    }
    ;
    c
    o
    n
    d
    i
    t
    i
    o
    n
    A
    w
    a
    i
    t
    e
    r = n
    e
    w C
    o
    n
    d
    i
    t
    i
    o
    n
    A
    w
    a
    i
    t
    e
    r
    (
    c
    a
    l
    l
    a
    b
    l
    e
    , s
    e
    t
    t
    i
    n
    g
    s
    ) {
    @
    O
    v
    e
    r
    r
    i
    d
    e
    p
    r
    o
    t
    e
    c
    t
    e
    d S
    t
    r
    i
    n
    g g
    e
    t
    T
    i
    m
    e
    o
    u
    t
    M
    e
    s
    s
    a
    g
    e
    (
    ) {
    r
    e
    t
    u
    r
    n s
    u
    p
    p
    l
    i
    e
    r
    .
    g
    e
    t
    C
    l
    a
    s
    s
    (
    )
    .
    g
    e
    t
    N
    a
    m
    e
    (
    ) + " " + l
    a
    s
    t
    E
    x
    c
    e
    p
    t
    i
    o
    n
    M
    e
    s
    s
    a
    g
    e
    ;
    }
    }
    ;
    }
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    1.6.0+
    

    View Slide

27. Case study 3:
    Mockito
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

28. Mockito - argument capturing
    Capture reference to object passed as argument in
    method call
    Alternative for matchers
    Useful for complex object verification
    A
    r
    g
    u
    m
    e
    n
    t
    C
    a
    p
    t
    o
    r
    <
    S
    h
    i
    p
    S
    e
    a
    r
    c
    h
    C
    r
    i
    t
    e
    r
    i
    a
    > c
    a
    p
    t
    o
    r =
    A
    r
    g
    u
    m
    e
    n
    t
    C
    a
    p
    t
    o
    r
    .
    f
    o
    r
    C
    l
    a
    s
    s
    (
    S
    h
    i
    p
    S
    e
    a
    r
    c
    h
    C
    r
    i
    t
    e
    r
    i
    a
    .
    c
    l
    a
    s
    s
    )
    ;
    v
    e
    r
    i
    f
    y
    (
    t
    s
    )
    .
    f
    i
    n
    d
    N
    u
    m
    b
    e
    r
    O
    f
    S
    h
    i
    p
    s
    I
    n
    R
    a
    n
    g
    e
    B
    y
    C
    r
    i
    t
    e
    r
    i
    a
    (
    c
    a
    p
    t
    o
    r
    .
    c
    a
    p
    t
    u
    r
    e
    (
    )
    )
    ;
    a
    s
    s
    e
    r
    t
    T
    h
    a
    t
    (
    c
    a
    p
    t
    o
    r
    .
    g
    e
    t
    V
    a
    l
    u
    e
    (
    )
    .
    g
    e
    t
    M
    i
    n
    i
    m
    u
    m
    R
    a
    n
    g
    e
    (
    )
    )
    .
    i
    s
    L
    e
    s
    s
    T
    h
    a
    n
    (
    2
    0
    0
    0
    )
    ;
    Bloated - 3 lines to assert one value
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

29. Mockito - argument capturing - Java 8
    Why not embed AssertJ inside a capturing call?
    v
    e
    r
    i
    f
    y
    (
    t
    s
    )
    .
    f
    i
    n
    d
    N
    u
    m
    b
    e
    r
    O
    f
    S
    h
    i
    p
    s
    I
    n
    R
    a
    n
    g
    e
    B
    y
    C
    r
    i
    t
    e
    r
    i
    a
    (
    a
    s
    s
    e
    r
    t
    A
    r
    g
    (
    s
    c -
    > a
    s
    s
    e
    r
    t
    T
    h
    a
    t
    (
    s
    c
    .
    g
    e
    t
    M
    i
    n
    i
    m
    u
    m
    R
    a
    n
    g
    e
    (
    )
    )
    .
    i
    s
    L
    e
    s
    s
    T
    h
    a
    n
    (
    2
    0
    0
    0
    )
    )
    )
    ;
    Clear and verbose error message from AssertJ
    A
    r
    g
    u
    m
    e
    n
    t a
    s
    s
    e
    r
    t
    i
    o
    n e
    r
    r
    o
    r
    :
    t
    s
    .
    f
    i
    n
    d
    N
    u
    m
    b
    e
    r
    O
    f
    S
    h
    i
    p
    s
    I
    n
    R
    a
    n
    g
    e
    B
    y
    C
    r
    i
    t
    e
    r
    i
    a
    (
    <
    a
    s
    s
    e
    r
    t
    i
    o
    n m
    a
    t
    c
    h
    e
    r
    >
    E
    x
    p
    e
    c
    t
    i
    n
    g
    :
    <
    3
    0
    0
    0
    >
    t
    o b
    e l
    e
    s
    s t
    h
    a
    n
    :
    <
    2
    0
    0
    0
    >
    )
    ;
    I
    n
    t
    e
    r
    a
    c
    t
    i
    o
    n
    s w
    i
    t
    h t
    h
    i
    s m
    o
    c
    k
    :
    t
    s
    .
    f
    i
    n
    d
    N
    u
    m
    b
    e
    r
    O
    f
    S
    h
    i
    p
    s
    I
    n
    R
    a
    n
    g
    e
    B
    y
    C
    r
    i
    t
    e
    r
    i
    a
    (
    S
    h
    i
    p
    S
    e
    a
    r
    c
    h
    C
    r
    i
    t
    e
    r
    i
    a
    {
    m
    i
    n
    i
    m
    u
    m
    R
    a
    n
    g
    e
    =
    3
    0
    0
    0
    , n
    u
    m
    b
    e
    r
    O
    f
    P
    h
    a
    s
    e
    r
    s
    =
    4
    }
    )
    ;
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

30. Mockito - argument capturing - internals
    p
    u
    b
    l
    i
    c c
    l
    a
    s
    s A
    s
    s
    e
    r
    t
    i
    o
    n
    M
    a
    t
    c
    h
    e
    r
    <
    T
    > e
    x
    t
    e
    n
    d
    s A
    r
    g
    u
    m
    e
    n
    t
    M
    a
    t
    c
    h
    e
    r
    <
    T
    > {
    (
    .
    .
    .
    )
    p
    u
    b
    l
    i
    c A
    s
    s
    e
    r
    t
    i
    o
    n
    M
    a
    t
    c
    h
    e
    r
    (
    C
    o
    n
    s
    u
    m
    e
    r
    <
    T
    > c
    o
    n
    s
    u
    m
    e
    r
    ) {
    t
    h
    i
    s
    .
    c
    o
    n
    s
    u
    m
    e
    r = c
    o
    n
    s
    u
    m
    e
    r
    ;
    }
    @
    O
    v
    e
    r
    r
    i
    d
    e
    p
    u
    b
    l
    i
    c b
    o
    o
    l
    e
    a
    n m
    a
    t
    c
    h
    e
    s
    (
    O
    b
    j
    e
    c
    t a
    r
    g
    u
    m
    e
    n
    t
    ) {
    t
    r
    y {
    c
    o
    n
    s
    u
    m
    e
    r
    .
    a
    c
    c
    e
    p
    t
    (
    (
    T
    ) a
    r
    g
    u
    m
    e
    n
    t
    )
    ;
    r
    e
    t
    u
    r
    n t
    r
    u
    e
    ;
    } c
    a
    t
    c
    h (
    A
    s
    s
    e
    r
    t
    i
    o
    n
    E
    r
    r
    o
    r e
    ) {
    e
    r
    r
    o
    r
    M
    e
    s
    s
    a
    g
    e = e
    .
    g
    e
    t
    M
    e
    s
    s
    a
    g
    e
    (
    )
    ;
    r
    e
    t
    u
    r
    n f
    a
    l
    s
    e
    ;
    }
    }
    @
    O
    v
    e
    r
    r
    i
    d
    e
    p
    u
    b
    l
    i
    c v
    o
    i
    d d
    e
    s
    c
    r
    i
    b
    e
    T
    o
    (
    D
    e
    s
    c
    r
    i
    p
    t
    i
    o
    n d
    e
    s
    c
    r
    i
    p
    t
    i
    o
    n
    ) { .
    .
    . }
    p
    u
    b
    l
    i
    c s
    t
    a
    t
    i
    c <
    T
    > T a
    s
    s
    e
    r
    t
    A
    r
    g
    (
    C
    o
    n
    s
    u
    m
    e
    r
    <
    T
    > c
    o
    n
    s
    u
    m
    e
    r
    ) {
    M
    o
    c
    k
    i
    t
    o
    .
    a
    r
    g
    T
    h
    a
    t
    (
    n
    e
    w A
    s
    s
    e
    r
    t
    i
    o
    n
    M
    a
    t
    c
    h
    e
    r
    <
    T
    >
    (
    c
    o
    n
    s
    u
    m
    e
    r
    )
    )
    ;
    r
    e
    t
    u
    r
    n h
    a
    n
    d
    y
    R
    e
    t
    u
    r
    n
    V
    a
    l
    u
    e
    s
    .
    r
    e
    t
    u
    r
    n
    S
    a
    f
    e
    N
    u
    l
    l
    (
    )
    ;
    }
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

31. Case study 4:
    catch-exception
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

32. Testing thrown exceptions - Java 7
    @Test(expected = ...)
    try..catch
    ExpectedException
    catch-exception
    fluent-exception-rule
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

33. catch-exception - Java 7
    catch and verify exceptions in a single line of code
    /
    /
    g
    i
    v
    e
    n
    L
    i
    s
    t
    <
    S
    t
    r
    i
    n
    g
    > m
    y
    L
    i
    s
    t = n
    e
    w A
    r
    r
    a
    y
    L
    i
    s
    t
    <
    >
    (
    )
    ;
    w
    h
    e
    n
    (
    m
    y
    L
    i
    s
    t
    )
    .
    g
    e
    t
    (
    1
    )
    ;
    t
    h
    e
    n
    (
    c
    a
    u
    g
    h
    t
    E
    x
    c
    e
    p
    t
    i
    o
    n
    (
    )
    )
    .
    i
    s
    I
    n
    s
    t
    a
    n
    c
    e
    O
    f
    (
    I
    n
    d
    e
    x
    O
    u
    t
    O
    f
    B
    o
    u
    n
    d
    s
    E
    x
    c
    e
    p
    t
    i
    o
    n
    .
    c
    l
    a
    s
    s
    )
    .
    h
    a
    s
    M
    e
    s
    s
    a
    g
    e
    (
    "
    I
    n
    d
    e
    x
    : 1
    , S
    i
    z
    e
    : 0
    "
    )
    .
    h
    a
    s
    N
    o
    C
    a
    u
    s
    e
    (
    )
    ;
    can use existing AssertJ assertions for exception instances
    no support for static methods and constructor calls
    complicated implementation
    proxy to remember and re-execute method call
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

34. catch-exception - Java 8
    What can be simplified with Java 8?
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

35. catch-exception - Java 8
    What can be simplified with Java 8?
    Everything...
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

36. catch-exception - Java 8
    What can be simplified with Java 8?
    Everything...
    From the project webpage:
    Java 8's lambda expressions will make catch-exception
    redundant.
    The project have been deprecated by the original author
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

37. catch-exception - Java 8
    The entire library (20+ classes) can be replaced with
    T
    h
    r
    o
    w
    a
    b
    l
    e c
    a
    p
    t
    u
    r
    e
    T
    h
    r
    o
    w
    a
    b
    l
    e
    (
    C
    a
    l
    l
    a
    b
    l
    e c
    a
    l
    l
    a
    b
    l
    e
    ) {
    t
    r
    y {
    c
    a
    l
    l
    a
    b
    l
    e
    .
    c
    a
    l
    l
    (
    )
    ;
    F
    a
    i
    l
    .
    f
    a
    i
    l
    (
    "
    E
    x
    p
    e
    c
    t
    i
    n
    g c
    o
    d
    e t
    o t
    h
    r
    o
    w a
    n e
    x
    c
    e
    p
    t
    i
    o
    n
    .
    "
    )
    ;
    r
    e
    t
    u
    r
    n n
    u
    l
    l
    ; /
    /
    t
    o s
    a
    t
    i
    s
    f
    y c
    o
    m
    p
    i
    l
    e
    r
    } c
    a
    t
    c
    h (
    T
    h
    r
    o
    w
    a
    b
    l
    e t
    h
    r
    o
    w
    a
    b
    l
    e
    ) {
    r
    e
    t
    u
    r
    n t
    h
    r
    o
    w
    a
    b
    l
    e
    ;
    }
    }
    And one line exception capture
    T
    h
    r
    o
    w
    a
    b
    l
    e t
    h
    r
    o
    w
    n = c
    a
    p
    t
    u
    r
    e
    T
    h
    r
    o
    w
    a
    b
    l
    e
    (
    (
    ) -
    > r
    i
    s
    k
    y
    M
    e
    t
    h
    o
    d
    (
    )
    )
    ;
    a
    s
    s
    e
    r
    t
    T
    h
    a
    t
    (
    t
    h
    r
    o
    w
    n
    )
    .
    .
    i
    s
    I
    n
    s
    t
    a
    n
    c
    e
    O
    f
    (
    I
    l
    l
    e
    g
    a
    l
    S
    t
    a
    t
    e
    E
    x
    c
    e
    p
    t
    i
    o
    n
    .
    c
    l
    a
    s
    s
    )
    .
    h
    a
    s
    M
    e
    s
    s
    a
    g
    e
    (
    "
    T
    e
    s
    t e
    x
    c
    e
    p
    t
    i
    o
    n
    "
    )
    ;
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

38. catch-exception
    Lambda approach already implemented in AssertJ
    Will be available in AssertJ 2.0
    @
    T
    e
    s
    t
    p
    u
    b
    l
    i
    c v
    o
    i
    d s
    h
    o
    u
    l
    d
    C
    a
    t
    c
    h
    E
    x
    c
    e
    p
    t
    i
    o
    n
    W
    i
    t
    h
    G
    o
    o
    d
    M
    e
    s
    s
    a
    g
    e
    (
    ) {
    a
    s
    s
    e
    r
    t
    T
    h
    a
    t
    E
    x
    c
    e
    p
    t
    i
    o
    n
    T
    h
    r
    o
    w
    n
    B
    y
    (
    (
    ) -
    > r
    i
    s
    k
    y
    M
    e
    t
    h
    o
    d
    (
    )
    )
    .
    i
    s
    I
    n
    s
    t
    a
    n
    c
    e
    O
    f
    (
    I
    l
    l
    e
    g
    a
    l
    S
    t
    a
    t
    e
    E
    x
    c
    e
    p
    t
    i
    o
    n
    .
    c
    l
    a
    s
    s
    )
    .
    h
    a
    s
    M
    e
    s
    s
    a
    g
    e
    (
    "
    T
    e
    s
    t e
    x
    c
    e
    p
    t
    i
    o
    n
    "
    )
    ;
    }
    Java 7 people can use maintenance fork by Mariusz
    Smykuła from Codearte
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

39. Summary
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

40. Summary
    More compact and smarter (testing) code with Java 8
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

41. Summary
    More compact and smarter (testing) code with Java 8
    Some things work out of the box
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

42. Summary
    More compact and smarter (testing) code with Java 8
    Some things work out of the box
    Lambdas alone do not replace everything
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

43. Summary
    More compact and smarter (testing) code with Java 8
    Some things work out of the box
    Lambdas alone do not replace everything
    Some tools have to be modified to benefit
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

44. Summary
    More compact and smarter (testing) code with Java 8
    Some things work out of the box
    Lambdas alone do not replace everything
    Some tools have to be modified to benefit
    Some tools were made obsolete completely...
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

45. Summary
    More compact and smarter (testing) code with Java 8
    Some things work out of the box
    Lambdas alone do not replace everything
    Some tools have to be modified to benefit
    Some tools were made obsolete completely...
    Sometimes it is required to change a mindset to see an
    oportunity
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

46. Summary
    More compact and smarter (testing) code with Java 8
    Some things work out of the box
    Lambdas alone do not replace everything
    Some tools have to be modified to benefit
    Some tools were made obsolete completely...
    Sometimes it is required to change a mindset to see an
    oportunity
    There is still a lot work to do in that field
    maybe it is worth to learn Java 8 features hacking some
    open source tool?
    Marcin Zajączkowski @SolidSoftBlog http://blog.solidsoft.info/
    

    View Slide

47. Questions/comments?
    During the next break or via Twitter
    Marcin Zajączkowski
    http://blog.solidsoft.info/
    @SolidSoftBlog
    m.zajaczkowski@gmail.com
    

    View Slide