Schema (kafka 0.10.0.1 API)

All Known Implementing Classes:

ConnectSchema, SchemaBuilder
```
public interface Schema
```
Definition of an abstract data type. Data types can be primitive types (integer types, floating point types, boolean, strings, and bytes) or complex types (typed arrays, maps with one key schema and value schema, and structs that have a fixed set of field names each with an associated value schema). Any type can be specified as optional, allowing it to be omitted (resulting in null values when it is missing) and can specify a default value.

All schemas may have some associated metadata: a name, version, and documentation. These are all considered part of the schema itself and included when comparing schemas. Besides adding important metadata, these fields enable the specification of logical types that specify additional constraints and semantics (e.g. UNIX timestamps are just an int64, but the user needs the know about the additional semantics to interpret it properly).

Schemas can be created directly, but in most cases using SchemaBuilder will be simpler.

Nested Class Summary

Nested Classes
Modifier and Type Interface and Description

static class Schema.Type
The type of a schema.

Nested Classes
Modifier and Type	Interface and Description
`static class`	`Schema.Type` The type of a schema.

Field Summary

Fields
Modifier and Type	Field and Description
`static Schema`	`BOOLEAN_SCHEMA`
`static Schema`	`BYTES_SCHEMA`
`static Schema`	`FLOAT32_SCHEMA`
`static Schema`	`FLOAT64_SCHEMA`
`static Schema`	`INT16_SCHEMA`
`static Schema`	`INT32_SCHEMA`
`static Schema`	`INT64_SCHEMA`
`static Schema`	`INT8_SCHEMA`
`static Schema`	`OPTIONAL_BOOLEAN_SCHEMA`
`static Schema`	`OPTIONAL_BYTES_SCHEMA`
`static Schema`	`OPTIONAL_FLOAT32_SCHEMA`
`static Schema`	`OPTIONAL_FLOAT64_SCHEMA`
`static Schema`	`OPTIONAL_INT16_SCHEMA`
`static Schema`	`OPTIONAL_INT32_SCHEMA`
`static Schema`	`OPTIONAL_INT64_SCHEMA`
`static Schema`	`OPTIONAL_INT8_SCHEMA`
`static Schema`	`OPTIONAL_STRING_SCHEMA`
`static Schema`	`STRING_SCHEMA`

Method Summary

Methods
Modifier and Type	Method and Description
`Object`	`defaultValue()`
`String`	`doc()`
`Field`	`field(String fieldName)` Get a field for this Schema by name.
`List<Field>`	`fields()` Get the list of fields for this Schema.
`boolean`	`isOptional()`
`Schema`	`keySchema()` Get the key schema for this map schema.
`String`	`name()`
`Map<String,String>`	`parameters()` Get a map of schema parameters.
`Schema`	`schema()` Return a concrete instance of the `Schema`
`Schema.Type`	`type()`
`Schema`	`valueSchema()` Get the value schema for this map or array schema.
`Integer`	`version()` Get the optional version of the schema.

- Field Detail
  - INT8_SCHEMA
```
static final Schema INT8_SCHEMA
```
  - INT16_SCHEMA
```
static final Schema INT16_SCHEMA
```
  - INT32_SCHEMA
```
static final Schema INT32_SCHEMA
```
  - INT64_SCHEMA
```
static final Schema INT64_SCHEMA
```
  - FLOAT32_SCHEMA
```
static final Schema FLOAT32_SCHEMA
```
  - FLOAT64_SCHEMA
```
static final Schema FLOAT64_SCHEMA
```
  - BOOLEAN_SCHEMA
```
static final Schema BOOLEAN_SCHEMA
```
  - STRING_SCHEMA
```
static final Schema STRING_SCHEMA
```
  - BYTES_SCHEMA
```
static final Schema BYTES_SCHEMA
```
  - OPTIONAL_INT8_SCHEMA
```
static final Schema OPTIONAL_INT8_SCHEMA
```
  - OPTIONAL_INT16_SCHEMA
```
static final Schema OPTIONAL_INT16_SCHEMA
```
  - OPTIONAL_INT32_SCHEMA
```
static final Schema OPTIONAL_INT32_SCHEMA
```
  - OPTIONAL_INT64_SCHEMA
```
static final Schema OPTIONAL_INT64_SCHEMA
```
  - OPTIONAL_FLOAT32_SCHEMA
```
static final Schema OPTIONAL_FLOAT32_SCHEMA
```
  - OPTIONAL_FLOAT64_SCHEMA
```
static final Schema OPTIONAL_FLOAT64_SCHEMA
```
  - OPTIONAL_BOOLEAN_SCHEMA
```
static final Schema OPTIONAL_BOOLEAN_SCHEMA
```
  - OPTIONAL_STRING_SCHEMA
```
static final Schema OPTIONAL_STRING_SCHEMA
```
  - OPTIONAL_BYTES_SCHEMA
```
static final Schema OPTIONAL_BYTES_SCHEMA
```
- Method Detail
  - type
```
Schema.Type type()
```
    Returns:
    the type of this schema
  - isOptional
```
boolean isOptional()
```
    Returns:
    true if this field is optional, false otherwise
  - defaultValue
```
Object defaultValue()
```
    Returns:
    the default value for this schema
  - name
```
String name()
```
    Returns:
    the name of this schema
  - version
```
Integer version()
```
    Get the optional version of the schema. If a version is included, newer versions *must* be larger than older ones.
    
    Returns:
    the version of this schema
  - doc
```
String doc()
```
    Returns:
    the documentation for this schema
  - parameters
```
Map<String,String> parameters()
```
    Get a map of schema parameters.
    
    Returns:
    Map containing parameters for this schema, or null if there are no parameters
  - keySchema
```
Schema keySchema()
```
    Get the key schema for this map schema. Throws a DataException if this schema is not a map.
    
    Returns:
    the key schema
  - valueSchema
```
Schema valueSchema()
```
    Get the value schema for this map or array schema. Throws a DataException if this schema is not a map or array.
    
    Returns:
    the value schema
  - fields
```
List<Field> fields()
```
    Get the list of fields for this Schema. Throws a DataException if this schema is not a struct.
    
    Returns:
    the list of fields for this Schema
  - field
```
Field field(String fieldName)
```
    Get a field for this Schema by name. Throws a DataException if this schema is not a struct.
    
    Parameters:
    fieldName - the name of the field to look up
    
    Returns:
    the Field object for the specified field, or null if there is no field with the given name
  - schema
```
Schema schema()
```
    Return a concrete instance of the Schema
    
    Returns:
    the Schema

Interface Schema

Nested Class Summary

Field Summary

Method Summary

Field Detail

INT8_SCHEMA

INT16_SCHEMA

INT32_SCHEMA

INT64_SCHEMA

FLOAT32_SCHEMA

FLOAT64_SCHEMA

BOOLEAN_SCHEMA

STRING_SCHEMA

BYTES_SCHEMA

OPTIONAL_INT8_SCHEMA

OPTIONAL_INT16_SCHEMA

OPTIONAL_INT32_SCHEMA

OPTIONAL_INT64_SCHEMA

OPTIONAL_FLOAT32_SCHEMA

OPTIONAL_FLOAT64_SCHEMA

OPTIONAL_BOOLEAN_SCHEMA

OPTIONAL_STRING_SCHEMA

OPTIONAL_BYTES_SCHEMA

Method Detail

type

isOptional

defaultValue

name

version

doc

parameters

keySchema

valueSchema

fields

field

schema