Package dev.relism.flash.models

Class HeaderMap

java.lang.Object

dev.relism.flash.models.HeaderMap

public class HeaderMap
extends Object

Lazy, zero-copy header access backed directly by the request parser's byte buffer. Strings are allocated only when first(java.lang.String) / all(java.lang.String) / view(java.lang.String) is called; the raw bytes are never copied at parse time.

Lifetime contract — read carefully

One HeaderMap instance lives on the connection (not per-request). On every keep-alive request reset(byte[], int, int) is called to slide the window over the new header section of the same reused buffer. This has two critical implications:

1. Do not retain the HeaderMap beyond the handler. After the handler returns, the next request reuses and overwrites the buffer. Any String values retrieved via first(java.lang.String)/all(java.lang.String) are safe (they are independent heap copies); the HeaderMap object itself is not.
2. view(java.lang.String) returns a zero-copy ByteView slice into the live buffer. Storing this view and reading it after the handler returns (e.g. in an async callback, a CompletableFuture continuation, or a virtual-thread handoff) is a data race — the bytes may have been overwritten by the next request. Copy to a String or byte[] before leaving the synchronous handler scope.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	HeaderMap.HeaderConsumer	Callback for forEach(dev.relism.flash.models.HeaderMap.HeaderConsumer).

Constructor Summary

Constructors

Constructor	Description
HeaderMap()

Method Summary

Modifier and Type	Method	Description
List<String>	all()	Returns all header values in declaration order.
List<String>	all(String name)	Returns all values of header name in declaration order, or an empty list.
String	first(String name)	Returns the first value of header name (case-insensitive), or null.
void	forEach(HeaderMap.HeaderConsumer consumer)	Visits every header in declaration order without allocating — no per-header String/ByteView/list-entry object, unlike all().
void	reset(byte[] buffer, int sectionStart, int sectionEnd)	Resets this map to the header section buffer[sectionStart, sectionEnd).
boolean	valueEqualsIgnoreCase(String name, String value)	Case-insensitive comparison of the first value of name against value.
dev.relism.fpr.core.ByteView	view(String name)	Returns a zero-copy ByteView over the first value of name, or null.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

HeaderMap

public HeaderMap()

Method Details

reset

public void reset(byte[] buffer,
 int sectionStart,
 int sectionEnd)

Resets this map to the header section buffer[sectionStart, sectionEnd).

forEach

public void forEach(HeaderMap.HeaderConsumer consumer)

Visits every header in declaration order without allocating — no per-header String/ByteView/list-entry object, unlike all(). name/ value are the same two ByteView instances on every call, repositioned in place; they are valid only for the duration of that single HeaderMap.HeaderConsumer.accept(dev.relism.fpr.core.ByteView, dev.relism.fpr.core.ByteView) call — same "do not retain past the handler" rule as view(java.lang.String), just per-invocation instead of per-request. Prefer a non-capturing or field-reusing HeaderMap.HeaderConsumer (see its javadoc) if the call site itself needs to stay allocation-free too.

Exists for callers that must handle an open-ended set of header names — e.g. a reverse proxy forwarding whatever the client sent — where first(java.lang.String)/all(java.lang.String)'s per-name lookup isn't usable because the set of names isn't known upfront.

first

public String first(String name)

Returns the first value of header name (case-insensitive), or null.

all

public List<String> all(String name)

Returns all values of header name in declaration order, or an empty list.

all

public List<String> all()

Returns all header values in declaration order.

valueEqualsIgnoreCase

public boolean valueEqualsIgnoreCase(String name,
 String value)

Case-insensitive comparison of the first value of name against value.

view

public dev.relism.fpr.core.ByteView view(String name)

Returns a zero-copy ByteView over the first value of name, or null.