Package io.opentelemetry.api.incubator.propagation

Class EnvironmentSetter

java.lang.Object

io.opentelemetry.api.incubator.propagation.EnvironmentSetter

All Implemented Interfaces:

io.opentelemetry.context.propagation.TextMapSetter<Map<String,String>>

public final class EnvironmentSetter
extends Object
implements io.opentelemetry.context.propagation.TextMapSetter<Map<String,String>>

A TextMapSetter that injects context into a map carrier, intended for use with environment variables when spawning child processes.

This is useful when an application needs to propagate context to sub-processes via their environment. For example, when using ProcessBuilder:

 Map<String, String> env = new HashMap<>();
 contextPropagators.getTextMapPropagator().inject(context, env, EnvironmentSetter.getInstance());
 ProcessBuilder processBuilder = new ProcessBuilder();
 processBuilder.environment().putAll(env);
 

This setter automatically sanitizes keys to be compatible with environment variable naming conventions:

• Converts keys to uppercase (e.g., traceparent becomes TRACEPARENT)
• Replaces . and - with underscores

Values are validated to contain only characters valid in HTTP header fields per RFC 9110 (visible ASCII characters, space, and horizontal tab). Values containing invalid characters are silently skipped.

Size limitations: Environment variable sizes are platform-dependent (e.g., Windows limits name=value pairs to 32,767 characters). Callers are responsible for being aware of platform-specific limits when injecting context.

See Also:

• Environment Variable Format Restrictions

Method Summary

Modifier and Type	Method	Description
static EnvironmentSetter	getInstance()	Returns the singleton instance of EnvironmentSetter.
void	set(Map<String,String> carrier, String key, String value)
String	toString()

Methods inherited from class java.lang.Object

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

Method Details

getInstance

public static EnvironmentSetter getInstance()

Returns the singleton instance of EnvironmentSetter.

set

public void set(@Nullable
 Map<String,String> carrier,
 String key,
 String value)

Specified by:

set in interface io.opentelemetry.context.propagation.TextMapSetter<Map<String,String>>

toString

public String toString()

Overrides:

toString in class Object