Class CachedCrnStringPatternMatcher<T>

java.lang.Object

io.confluent.crn.CachedCrnStringPatternMatcher<T>

public class CachedCrnStringPatternMatcher<T>
extends Object

In practice, we will usually be routing messages based on the string CRN values in CloudEvent subject fields. This cache avoids the expense of parsing those strings into ConfluentResourceNames, and the expense of re-evaluating the CRN against a probably-unchanging set of rules.

We assume that the number of unique subjects that we'll route based on is not unreasonably large. There may be, eg. tens of thousands of topics, but not billions. We use an LRU to make sure we don't expand the cache indefinitely.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	CachedCrnStringPatternMatcher.Builder<T>

Constructor Summary

Constructors

Constructor	Description
CachedCrnStringPatternMatcher(CrnPatternMatcher<T> matcher, int capacity)	Create a cache with the desired capacity.

Method Summary

Modifier and Type	Method	Description
static <T> CachedCrnStringPatternMatcher.Builder<T>	builder()
T	match(String crnString)	Return the stored value for this CRN, or null if there is no match
int	size()
String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Details

CachedCrnStringPatternMatcher

public CachedCrnStringPatternMatcher(CrnPatternMatcher<T> matcher,
 int capacity)

Create a cache with the desired capacity. The capacity should be tuned to the number of unique CRNs that will be matched, not the number of patterns they will be matched against. If you have 1000 different topics, but 10 rules, the capacity should be > 1000.

Method Details

builder

public static <T>
CachedCrnStringPatternMatcher.Builder<T> builder()

match

public T match(String crnString)

Return the stored value for this CRN, or null if there is no match

size

public int size()

toString

public String toString()

Overrides:

toString in class Object