java.lang.Object
- io.objectbox.flatbuffers.FlexBuffersBuilder

```
public class FlexBuffersBuilder
extends java.lang.Object
```
Helper class that builds FlexBuffers
This class presents all necessary APIs to create FlexBuffers. A `ByteBuffer` will be used to store the data. It can be created internally, or passed down in the constructor.

There are some limitations when compared to original implementation in C++. Most notably:
- No support for mutations (might change in the future).
- Buffer size limited to Integer.MAX_VALUE
- Since Java does not support unsigned type, all unsigned operations accepts an immediate higher representation of similar type.

Nested Class Summary

Nested Classes
Modifier and Type Class Description

private static class FlexBuffersBuilder.Value

Field Summary

Fields
Modifier and Type	Field	Description
`private ReadWriteBuf`	`bb`
`static int`	`BUILDER_FLAG_NONE`	No keys or strings will be shared
`static int`	`BUILDER_FLAG_SHARE_ALL`	Reserved for the future.
`static int`	`BUILDER_FLAG_SHARE_KEY_VECTORS`	Reserved for the future.
`static int`	`BUILDER_FLAG_SHARE_KEYS`	Keys will be shared between elements.
`static int`	`BUILDER_FLAG_SHARE_KEYS_AND_STRINGS`	Strings and keys will be shared between elements.
`static int`	`BUILDER_FLAG_SHARE_STRINGS`	Strings will be shared between elements.
`private boolean`	`finished`
`private int`	`flags`
`private java.util.Comparator<FlexBuffersBuilder.Value>`	`keyComparator`
`private java.util.HashMap<java.lang.String,java.lang.Integer>`	`keyPool`
`private java.util.ArrayList<FlexBuffersBuilder.Value>`	`stack`
`private java.util.HashMap<java.lang.String,java.lang.Integer>`	`stringPool`
`private static int`	`WIDTH_16`
`private static int`	`WIDTH_32`
`private static int`	`WIDTH_64`
`private static int`	`WIDTH_8`

Constructor Summary

Constructors
Constructor	Description
`FlexBuffersBuilder()`	Constructs a newly allocated `FlexBuffersBuilder` with `BUILDER_FLAG_SHARE_KEYS` set.
`FlexBuffersBuilder(int bufSize)`	Constructs a newly allocated `FlexBuffersBuilder` with `BUILDER_FLAG_SHARE_KEYS` set.
`FlexBuffersBuilder(ReadWriteBuf bb, int flags)`
`FlexBuffersBuilder(java.nio.ByteBuffer bb)`	Constructs a newly allocated `FlexBuffersBuilder`.
`FlexBuffersBuilder(java.nio.ByteBuffer bb, int flags)`	Deprecated.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`private int`	`align(int alignment)`
`void`	`clear()`	Reset the FlexBuffersBuilder by purging all data that it holds.
`private FlexBuffersBuilder.Value`	`createKeyVector(int start, int length)`
`private FlexBuffersBuilder.Value`	`createVector(int key, int start, int length, boolean typed, boolean fixed, FlexBuffersBuilder.Value keys)`
`int`	`endMap(java.lang.String key, int start)`	Finishes a map, but writing the information in the buffer
`int`	`endVector(java.lang.String key, int start, boolean typed, boolean fixed)`	Finishes a vector, but writing the information in the buffer
`java.nio.ByteBuffer`	`finish()`	Finish writing the message into the buffer.
`ReadWriteBuf`	`getBuffer()`	Return `ByteBuffer` containing FlexBuffer message.
`int`	`putBlob(byte[] value)`	Adds a byte array into the message
`int`	`putBlob(java.lang.String key, byte[] val)`	Adds a byte array into the message
`void`	`putBoolean(boolean val)`	Insert a single boolean into the buffer
`void`	`putBoolean(java.lang.String key, boolean val)`	Insert a single boolean into the buffer
`void`	`putFloat(double value)`	Adds a 64-bit float into the buff.
`void`	`putFloat(float value)`	Adds a 32-bit float into the buff.
`void`	`putFloat(java.lang.String key, double val)`	Adds a 64-bit float into the buff.
`void`	`putFloat(java.lang.String key, float val)`	Adds a 32-bit float into the buff.
`void`	`putInt(int val)`	Adds a integer into the buff
`void`	`putInt(long value)`	Adds a 64-bit integer into the buff
`void`	`putInt(java.lang.String key, int val)`	Adds a integer into the buff
`void`	`putInt(java.lang.String key, long val)`	Adds a integer into the buff
`private int`	`putKey(java.lang.String key)`
`void`	`putNull()`	Insert a null value into the buffer
`void`	`putNull(java.lang.String key)`	Insert a null value into the buffer
`int`	`putString(java.lang.String value)`	Adds a String into the buffer
`int`	`putString(java.lang.String key, java.lang.String val)`	Adds a String into the buffer
`void`	`putUInt(int value)`	Adds a unsigned integer into the buff.
`void`	`putUInt(long value)`	Adds a unsigned integer (stored in a signed 64-bit integer) into the buff.
`private void`	`putUInt(java.lang.String key, long value)`
`private void`	`putUInt64(java.lang.String key, long value)`
`void`	`putUInt64(java.math.BigInteger value)`	Adds a 64-bit unsigned integer (stored as `BigInteger`) into the buff.
`int`	`startMap()`	Start a new map in the buffer.
`int`	`startVector()`	Start a new vector in the buffer.
`(package private) static int`	`widthUInBits(long len)`
`private void`	`writeAny(FlexBuffersBuilder.Value val, int byteWidth)`
`private FlexBuffersBuilder.Value`	`writeBlob(int key, byte[] blob, int type, boolean trailing)`
`private void`	`writeDouble(double val, int byteWidth)`
`private void`	`writeInt(long value, int byteWidth)`
`private void`	`writeOffset(long val, int byteWidth)`
`private FlexBuffersBuilder.Value`	`writeString(int key, java.lang.String s)`

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

- Field Detail
  - BUILDER_FLAG_NONE
```
public static final int BUILDER_FLAG_NONE
```
    No keys or strings will be shared
    
    See Also:
    
    Constant Field Values
  - BUILDER_FLAG_SHARE_KEYS
```
public static final int BUILDER_FLAG_SHARE_KEYS
```
    Keys will be shared between elements. Identical keys will only be serialized once, thus possibly saving space. But serialization performance might be slower and consumes more memory.
    
    See Also:
    
    Constant Field Values
  - BUILDER_FLAG_SHARE_STRINGS
```
public static final int BUILDER_FLAG_SHARE_STRINGS
```
    Strings will be shared between elements. Identical strings will only be serialized once, thus possibly saving space. But serialization performance might be slower and consumes more memory. This is ideal if you expect many repeated strings on the message.
    
    See Also:
    
    Constant Field Values
  - BUILDER_FLAG_SHARE_KEYS_AND_STRINGS
```
public static final int BUILDER_FLAG_SHARE_KEYS_AND_STRINGS
```
    Strings and keys will be shared between elements.
    
    See Also:
    
    Constant Field Values
  - BUILDER_FLAG_SHARE_KEY_VECTORS
```
public static final int BUILDER_FLAG_SHARE_KEY_VECTORS
```
    Reserved for the future.
    
    See Also:
    
    Constant Field Values
  - BUILDER_FLAG_SHARE_ALL
```
public static final int BUILDER_FLAG_SHARE_ALL
```
    Reserved for the future.
    
    See Also:
    
    Constant Field Values
  - WIDTH_8
```
private static final int WIDTH_8
```
    See Also:
    
    Constant Field Values
  - WIDTH_16
```
private static final int WIDTH_16
```
    See Also:
    
    Constant Field Values
  - WIDTH_32
```
private static final int WIDTH_32
```
    See Also:
    
    Constant Field Values
  - WIDTH_64
```
private static final int WIDTH_64
```
    See Also:
    
    Constant Field Values
  - bb
```
private final ReadWriteBuf bb
```
  - stack
```
private final java.util.ArrayList<FlexBuffersBuilder.Value> stack
```
  - keyPool
```
private final java.util.HashMap<java.lang.String,java.lang.Integer> keyPool
```
  - stringPool
```
private final java.util.HashMap<java.lang.String,java.lang.Integer> stringPool
```
  - flags
```
private final int flags
```
  - finished
```
private boolean finished
```
  - keyComparator
```
private java.util.Comparator<FlexBuffersBuilder.Value> keyComparator
```
- Constructor Detail
  - FlexBuffersBuilder
```
public FlexBuffersBuilder(int bufSize)
```
    Constructs a newly allocated FlexBuffersBuilder with BUILDER_FLAG_SHARE_KEYS set.
    
    Parameters:
    
    bufSize - size of buffer in bytes.
  - FlexBuffersBuilder
```
public FlexBuffersBuilder()
```
    Constructs a newly allocated FlexBuffersBuilder with BUILDER_FLAG_SHARE_KEYS set.
  - FlexBuffersBuilder
```
@Deprecated
public FlexBuffersBuilder(java.nio.ByteBuffer bb,
                          int flags)
```
    Deprecated.
    
    Constructs a newly allocated FlexBuffersBuilder.
    
    Parameters:
    
    bb - `ByteBuffer` that will hold the message
    
    flags - Share flags
  - FlexBuffersBuilder
```
public FlexBuffersBuilder(ReadWriteBuf bb,
                          int flags)
```
  - FlexBuffersBuilder
```
public FlexBuffersBuilder(java.nio.ByteBuffer bb)
```
    Constructs a newly allocated FlexBuffersBuilder. By default same keys will be serialized only once
    
    Parameters:
    
    bb - `ByteBuffer` that will hold the message
- Method Detail
  - clear
```
public void clear()
```
    Reset the FlexBuffersBuilder by purging all data that it holds.
  - getBuffer
```
public ReadWriteBuf getBuffer()
```
    Return `ByteBuffer` containing FlexBuffer message. #finish() must be called before calling this function otherwise an assert will trigger.
    
    Returns:
    
    `ByteBuffer` with finished message
  - putNull
```
public void putNull()
```
    Insert a null value into the buffer
  - putNull
```
public void putNull(java.lang.String key)
```
    Insert a null value into the buffer
    
    Parameters:
    
    key - key used to store element in map
  - putBoolean
```
public void putBoolean(boolean val)
```
    Insert a single boolean into the buffer
    
    Parameters:
    
    val - true or false
  - putBoolean
```
public void putBoolean(java.lang.String key,
                       boolean val)
```
    Insert a single boolean into the buffer
    
    Parameters:
    
    key - key used to store element in map
    
    val - true or false
  - putKey
```
private int putKey(java.lang.String key)
```
  - putInt
```
public void putInt(int val)
```
    Adds a integer into the buff
    
    Parameters:
    
    val - integer
  - putInt
```
public void putInt(java.lang.String key,
                   int val)
```
    Adds a integer into the buff
    
    Parameters:
    
    key - key used to store element in map
    
    val - integer
  - putInt
```
public void putInt(java.lang.String key,
                   long val)
```
    Adds a integer into the buff
    
    Parameters:
    
    key - key used to store element in map
    
    val - 64-bit integer
  - putInt
```
public void putInt(long value)
```
    Adds a 64-bit integer into the buff
    
    Parameters:
    
    value - integer
  - putUInt
```
public void putUInt(int value)
```
    Adds a unsigned integer into the buff.
    
    Parameters:
    
    value - integer representing unsigned value
  - putUInt
```
public void putUInt(long value)
```
    Adds a unsigned integer (stored in a signed 64-bit integer) into the buff.
    
    Parameters:
    
    value - integer representing unsigned value
  - putUInt64
```
public void putUInt64(java.math.BigInteger value)
```
    Adds a 64-bit unsigned integer (stored as BigInteger) into the buff. Warning: This operation might be very slow.
    
    Parameters:
    
    value - integer representing unsigned value
  - putUInt64
```
private void putUInt64(java.lang.String key,
                       long value)
```
  - putUInt
```
private void putUInt(java.lang.String key,
                     long value)
```
  - putFloat
```
public void putFloat(float value)
```
    Adds a 32-bit float into the buff.
    
    Parameters:
    
    value - float representing value
  - putFloat
```
public void putFloat(java.lang.String key,
                     float val)
```
    Adds a 32-bit float into the buff.
    
    Parameters:
    
    key - key used to store element in map
    
    value - float representing value
  - putFloat
```
public void putFloat(double value)
```
    Adds a 64-bit float into the buff.
    
    Parameters:
    
    value - float representing value
  - putFloat
```
public void putFloat(java.lang.String key,
                     double val)
```
    Adds a 64-bit float into the buff.
    
    Parameters:
    
    key - key used to store element in map
    
    value - float representing value
  - putString
```
public int putString(java.lang.String value)
```
    Adds a String into the buffer
    
    Parameters:
    
    value - string
    
    Returns:
    
    start position of string in the buffer
  - putString
```
public int putString(java.lang.String key,
                     java.lang.String val)
```
    Adds a String into the buffer
    
    Parameters:
    
    key - key used to store element in map
    
    value - string
    
    Returns:
    
    start position of string in the buffer
  - writeString
```
private FlexBuffersBuilder.Value writeString(int key,
                                             java.lang.String s)
```
  - widthUInBits
```
static int widthUInBits(long len)
```
  - writeBlob
```
private FlexBuffersBuilder.Value writeBlob(int key,
                                           byte[] blob,
                                           int type,
                                           boolean trailing)
```
  - align
```
private int align(int alignment)
```
  - writeInt
```
private void writeInt(long value,
                      int byteWidth)
```
  - putBlob
```
public int putBlob(byte[] value)
```
    Adds a byte array into the message
    
    Parameters:
    
    value - byte array
    
    Returns:
    
    position in buffer as the start of byte array
  - putBlob
```
public int putBlob(java.lang.String key,
                   byte[] val)
```
    Adds a byte array into the message
    
    Parameters:
    
    key - key used to store element in map
    
    value - byte array
    
    Returns:
    
    position in buffer as the start of byte array
  - startVector
```
public int startVector()
```
    Start a new vector in the buffer.
    
    Returns:
    
    a reference indicating position of the vector in buffer. This reference must be passed along when the vector is finished using endVector()
  - endVector
```
public int endVector(java.lang.String key,
                     int start,
                     boolean typed,
                     boolean fixed)
```
    Finishes a vector, but writing the information in the buffer
    
    Parameters:
    
    key - key used to store element in map
    
    start - reference for beginning of the vector. Returned by startVector()
    
    typed - boolean indicating whether vector is typed
    
    fixed - boolean indicating whether vector is fixed
    
    Returns:
    
    Reference to the vector
  - finish
```
public java.nio.ByteBuffer finish()
```
    Finish writing the message into the buffer. After that no other element must be inserted into the buffer. Also, you must call this function before start using the FlexBuffer message
    
    Returns:
    
    `ByteBuffer` containing the FlexBuffer message
  - createVector
```
private FlexBuffersBuilder.Value createVector(int key,
                                              int start,
                                              int length,
                                              boolean typed,
                                              boolean fixed,
                                              FlexBuffersBuilder.Value keys)
```
  - writeOffset
```
private void writeOffset(long val,
                         int byteWidth)
```
  - writeAny
```
private void writeAny(FlexBuffersBuilder.Value val,
                      int byteWidth)
```
  - writeDouble
```
private void writeDouble(double val,
                         int byteWidth)
```
  - startMap
```
public int startMap()
```
    Start a new map in the buffer.
    
    Returns:
    
    a reference indicating position of the map in buffer. This reference must be passed along when the map is finished using endMap()
  - endMap
```
public int endMap(java.lang.String key,
                  int start)
```
    Finishes a map, but writing the information in the buffer
    
    Parameters:
    
    key - key used to store element in map
    
    start - reference for beginning of the map. Returned by startMap()
    
    Returns:
    
    Reference to the map
  - createKeyVector
```
private FlexBuffersBuilder.Value createKeyVector(int start,
                                                 int length)
```

Class FlexBuffersBuilder

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

BUILDER_FLAG_NONE

BUILDER_FLAG_SHARE_KEYS

BUILDER_FLAG_SHARE_STRINGS

BUILDER_FLAG_SHARE_KEYS_AND_STRINGS

BUILDER_FLAG_SHARE_KEY_VECTORS

BUILDER_FLAG_SHARE_ALL

WIDTH_8

WIDTH_16

WIDTH_32

WIDTH_64

bb

stack

keyPool

stringPool

flags

finished

keyComparator

Constructor Detail

FlexBuffersBuilder

FlexBuffersBuilder

FlexBuffersBuilder

FlexBuffersBuilder

FlexBuffersBuilder

Method Detail

clear

getBuffer

putNull

putNull

putBoolean

putBoolean

putKey

putInt

putInt

putInt

putInt

putUInt

putUInt

putUInt64

putUInt64

putUInt

putFloat

putFloat

putFloat

putFloat

putString

putString

writeString

widthUInBits

writeBlob

align

writeInt

putBlob

putBlob

startVector

endVector

finish

createVector

writeOffset

writeAny

writeDouble

startMap

endMap

createKeyVector