DnsQueryIdSpace

java.lang.Object
- io.netty.resolver.dns.DnsQueryIdSpace

```
final class DnsQueryIdSpace
extends java.lang.Object
```
Special data-structure that will allow to retrieve the next query id to use, while still guarantee some sort of randomness. The query id will be between 0 (inclusive) and 65535 (inclusive) as defined by the RFC.

Nested Class Summary

Nested Classes
Modifier and Type Class Description

private static class DnsQueryIdSpace.DnsQueryIdRange
Provides a query if from a range of possible ids.

Field Summary

Fields
Modifier and Type	Field	Description
`private static int`	`BUCKET_DROP_THRESHOLD`
`private static int`	`BUCKET_SIZE`
`private static int`	`BUCKETS`
`private DnsQueryIdSpace.DnsQueryIdRange[]`	`idBuckets`
`private static int`	`MAX_ID`
`private java.security.SecureRandom`	`random`

Constructor Summary

Constructors
Constructor Description

DnsQueryIdSpace()

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`(package private) int`	`maxUsableIds()`	Return the maximum number of ids that are supported.
`private static DnsQueryIdSpace.DnsQueryIdRange`	`newBucket(int idBucketsIdx, java.security.SecureRandom random)`
`(package private) int`	`nextId()`	Returns the next ID to use for a query or `-1` if there is none left to use.
`(package private) void`	`pushId(int id)`	Push back the id, so it can be used again for the next query.
`(package private) int`	`usableIds()`	Return how much more usable ids are left.

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

- Field Detail
  - MAX_ID
```
private static final int MAX_ID
```
    See Also:
    
    Constant Field Values
  - BUCKETS
```
private static final int BUCKETS
```
    See Also:
    
    Constant Field Values
  - BUCKET_SIZE
```
private static final int BUCKET_SIZE
```
    See Also:
    
    Constant Field Values
  - BUCKET_DROP_THRESHOLD
```
private static final int BUCKET_DROP_THRESHOLD
```
    See Also:
    
    Constant Field Values
  - idBuckets
```
private final DnsQueryIdSpace.DnsQueryIdRange[] idBuckets
```
  - random
```
private final java.security.SecureRandom random
```
- Constructor Detail
  - DnsQueryIdSpace
```
DnsQueryIdSpace()
```
- Method Detail
  - newBucket
```
private static DnsQueryIdSpace.DnsQueryIdRange newBucket(int idBucketsIdx,
                                                         java.security.SecureRandom random)
```
  - nextId
```
int nextId()
```
    Returns the next ID to use for a query or -1 if there is none left to use.
    
    Returns:
    
    next id to use.
  - pushId
```
void pushId(int id)
```
    Push back the id, so it can be used again for the next query.
    
    Parameters:
    
    id - the id.
  - usableIds
```
int usableIds()
```
    Return how much more usable ids are left.
    
    Returns:
    
    the number of ids that are left for usage.
  - maxUsableIds
```
int maxUsableIds()
```
    Return the maximum number of ids that are supported.
    
    Returns:
    
    the maximum number of ids.