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reflow paragraphs in section 12 #15

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26 changes: 19 additions & 7 deletions 12-annotations.md
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Original file line number Diff line number Diff line change
@@ -1,7 +1,8 @@
Annotation Improvements
-------

There are couple of improvements made in the annotation mechanism in Java 8. These are:
There are couple of improvements made in the annotation mechanism in Java 8.
These are:

1. Repeatable annotations
2. Type annotations
Expand All @@ -10,7 +11,10 @@ There are couple of improvements made in the annotation mechanism in Java 8. The

## Repeatable annotations

Before Java 8, it was not possible to use same annotation twice at the same location i.e. you can't use annotation `@Foo` twice on a method. If you have used JPA then you would have use an annotation called `@JoinColumns` that allows wraps multiple `@JoinColumn` annotation as shown below.
Before Java 8, it was not possible to use same annotation twice at the same
location i.e. you can't use annotation `@Foo` twice on a method. If you have
used JPA then you would have use an annotation called `@JoinColumns` that allows
wraps multiple `@JoinColumn` annotation as shown below.

```java
@ManyToOne
Expand All @@ -30,14 +34,18 @@ In Java 8, you can write the same as shown below because with Java 8 you can rep
public Address getAddress() { return address; }
```


***With Java 8 you can use same annotation type multiple times possibly with different arguments at any location(class, method, field declaration) in your Java code.***
***With Java 8 you can use same annotation type multiple times possibly with
different arguments at any location(class, method, field declaration) in your
Java code.***

### Writing your own repeatable Annotations

To write your own repeatable annotation you have to do the following:

**Step 1:** Create an annotation with `@Repeatable` annotation as shown below. `@Repeatable` annotation requires you to specify a mandatory value for the container type that will contain the annotation. We will create container annotation in step 2.
**Step 1:** Create an annotation with `@Repeatable` annotation as shown below.
`@Repeatable` annotation requires you to specify a mandatory value for the
container type that will contain the annotation. We will create container
annotation in step 2.

```java
import java.lang.annotation.*;
Expand Down Expand Up @@ -70,7 +78,10 @@ public void manage() {
}
```

If you have to find all the repeatable annotations on a method then you can use `getAnnotationsByType` method that is now available on `java.lang.Class` and `java.lang.reflect.Method`. To print all the vm names, you can write code as shown below.
If you have to find all the repeatable annotations on a method then you can use
`getAnnotationsByType` method that is now available on `java.lang.Class` and
`java.lang.reflect.Method`. To print all the vm names, you can write code as
shown below.

```java
CreateVm[] createVms = VmManager.class.getMethod("manage").getAnnotationsByType(CreateVm.class);
Expand All @@ -79,7 +90,8 @@ Stream.of(createVms).map(CreateVm::name).forEach(System.out::println);

## Type annotations

You can now apply annotations at two more target locations -- TYPE_PARAMETER and TYPE_USE.
You can now apply annotations at two more target locations -- TYPE_PARAMETER and
TYPE_USE.

```java
@Retention(RetentionPolicy.RUNTIME)
Expand Down