# Java

**Java** is the target language **by default**, so you don't have to define it explicitly. 

However, you can define it with the following instruction :

```
#set( $env.language = 'Java' )
```

The information below shows the behavior of the generator when Java is the current target language. For a detailed description of type conversion, see the generated documentation :   \
<https://www.telosys.org/doc/latest/languages/language-java.html> <br>

## Types conversion&#x20;

The table below describes how model neutral types are automatically converted to Java types with potential impact due to attribute annotations.

| Model type    | Java type                                                                                     | with annotation                          |
| ------------- | --------------------------------------------------------------------------------------------- | ---------------------------------------- |
| string        | **String**                                                                                    |                                          |
| byte          | <p><strong>Byte</strong><br><strong>byte</strong><br><strong>byte</strong></p>                | <p></p><p>@NotNull<br>@PrimitiveType</p> |
| short         | <p><strong>Short</strong></p><p><strong>short</strong></p><p><strong>short</strong></p>       | <p></p><p>@NotNull<br>@PrimitiveType</p> |
| int           | <p><strong>Integer</strong><br><strong>int</strong></p><p><strong>int</strong></p>            | <p></p><p>@NotNull<br>@PrimitiveType</p> |
| long          | <p><strong>Long</strong></p><p><strong>long</strong></p><p><strong>long</strong></p>          | <p></p><p>@NotNull<br>@PrimitiveType</p> |
| decimal       | **BigDecimal**                                                                                | <p></p><p></p>                           |
| float         | <p><strong>Float</strong></p><p><strong>float</strong></p><p><strong>float</strong></p>       | <p></p><p>@NotNull<br>@PrimitiveType</p> |
| double        | <p><strong>Double</strong></p><p><strong>double</strong></p><p><strong>double</strong></p>    | <p></p><p>@NotNull<br>@PrimitiveType</p> |
| boolean       | <p><strong>Boolean</strong></p><p><strong>boolean</strong></p><p><strong>boolean</strong></p> | <p></p><p>@NotNull<br>@PrimitiveType</p> |
| date          | **LocalDate**                                                                                 |                                          |
| time          | **LocalTime**                                                                                 |                                          |
| timetz        | **OffsetTime**                                                                                |                                          |
| datetime      | **LocalDateTime**                                                                             |                                          |
| datetimetz    | **OffsetDateTime**                                                                            |                                          |
| ~~timestamp~~ | **LocalDateTime**                                                                             |                                          |
| uuid          | **UUID**                                                                                      |                                          |
| binary        | **byte \[ ]**                                                                                 |                                          |

### Annotations effects

* **@UnsignedType** \
  no effect (all numeric types are signed in Java)
* **@ObjectType** \
  switches to the standard wrapper type for the current type \
  (Byte, Short, Integer, Long, Float, Double, Boolean)
* **@PrimitiveType** \
  switches to the primitive type if possible\
  (byte, short, int, long, float, double, boolean)
* **@NotNull** \
  switches to primitive type if possible in order to avoid 'null' value

### Specific types&#x20;

* &#x20;**$attribute.fullType**
  * for an "object type" returns the fully-qualified class name \
    (java.lang.String,  java.lang.Integer,  java.math.BigDecimal, etc )
  * for a "primitive type" returns the primitive type as is&#x20;

    ( int,  double,  etc )
* &#x20;**$attribute.simpleType**&#x20;
  * for an "object type" returns the simple class name\
    ( String,  Integer,  Double, etc )
  * for a "primitive type" returns the primitive type as is

    ( int,  double,  etc )
* &#x20;**$attribute.wrapperType** \
  returns the Java wrapper type class associtated with the current type (Integer, Double, etc )

## Literal values

#### TRUE, FALSE, NULL

|       | Java  literal |
| ----- | ------------- |
| TRUE  | **true**      |
| FALSE | **false**     |
| NULL  | **null**      |


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://doc.telosys.org/target-languages/java.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.