Package nl.colorize.util.http

Class Headers

java.lang.Object

nl.colorize.util.http.Headers

All Implemented Interfaces:

Iterable<Tuple<String,String>>

public class Headers
extends Object
implements Iterable<Tuple<String,String>>

Immutable representation of the request/response headers sent as part of an HTTP request. Used in conjunction with URLLoader, which supports a variety of HTTP clients depending on the platform.

HTTP headers are sometimes represented using a Map<String, String>, but this does not allow for the following:

• Headers have an explicitly defined order.
• The same header can occur multiple times.
• Header names are case-insensitive.

Constructor Summary

Constructors

Constructor	Description
Headers(TupleList<String,String> entries)	Creates a new Headers instance from the specified list of HTTP header names/values.

Method Summary

Modifier and Type	Method	Description
void	forEach(BiConsumer<String,String> callback)
static Headers	fromMap(Map<String,String> entries)	Creates a Headers instance from a map containing the name/value pairs of the HTTP headers.
Optional<String>	get(String name)	Returns the value of the header with the specified name.
List<String>	getAll(String name)	Returns all values for headers with the specified name.
List<String>	getHeaderNames()	Iterates over header names.
Iterator<Tuple<String,String>>	iterator()
static Headers	none()	Returns an empty Headers instance that indicates the HTTP request or response does not contain any headers.
static Headers	of(String name, String value, String... rest)	Creates a Headers instance from the specified HTTP header names and values.
String	toString()
static void	validateHeader(String name, String value)	Helper method that validates if the specified name and value should be allowed as a HTTP headers.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Details

Headers

public Headers(TupleList<String,String> entries)

Creates a new Headers instance from the specified list of HTTP header names/values. This class also defines a number of static factory methods for creating a Headers instance from other sources.

Throws:

IllegalArgumentException - if any of the header names and/or values are invalid. validateHeader(String, String) is used to perform this validation.

Method Details

getHeaderNames

public List<String> getHeaderNames()

Iterates over header names. Note that header names can appear multiple times in the list, if there are multiple occurrences of that header.

get

public Optional<String> get(String name)

Returns the value of the header with the specified name. If the header occurs multiple times, the first occurrence is returned.

getAll

public List<String> getAll(String name)

Returns all values for headers with the specified name. If the header is not present, this will return an empty list.

iterator

public Iterator<Tuple<String,String>> iterator()

Specified by:

iterator in interface Iterable<Tuple<String,String>>

forEach

public void forEach(BiConsumer<String,String> callback)

toString

public String toString()

Overrides:

toString in class Object

of

public static Headers of(String name,
 String value,
 String... rest)

Creates a Headers instance from the specified HTTP header names and values. The rest parameter expects values in the order name1, value1, name2, value2, ....

Throws:

IllegalArgumentException - When an odd number of arguments is passed to the method.

fromMap

public static Headers fromMap(Map<String,String> entries)

Creates a Headers instance from a map containing the name/value pairs of the HTTP headers. The order of the headers is based on the map's iteration order.

none

public static Headers none()

Returns an empty Headers instance that indicates the HTTP request or response does not contain any headers.

validateHeader

public static void validateHeader(String name,
 String value)

Helper method that validates if the specified name and value should be allowed as a HTTP headers.

Throws:

IllegalArgumentException - if the validation fails for the header name and/or value.