ServerSentEvent Chilkat2 Java Reference Documentation
ServerSentEvent
Current Version: 11.7.0
Markdown version of this page for AI tools (v 11.7.0) · all AI docs
Chilkat.ServerSentEvent
Use
Inspect
Use
Read
Use
Check Parse server-sent event text into event name, data, ID, and retry fields.
Chilkat.ServerSentEvent is a small helper class for parsing
Server-Sent Events formatted text. Given a multi-line event block, it
extracts the event name, data payload,
id value, and retry interval into simple
read-only properties. It is useful when an application receives event-stream
text and needs to work with the structured event fields instead of manually
parsing the raw lines.
Load event text
LoadEvent to parse a complete multi-line
Server-Sent Event block.
Read event name
EventName to determine the event type supplied by
the server, if an event: field is present.
Read event data
Data to obtain the event payload, such as JSON text from
a streaming API or real-time service.
Track event IDs
LastEventId when the event includes an
id: field that identifies the event or stream position.
Handle retry hints
Retry to read the server-provided retry interval when a
retry: field is included.
Diagnostics
LastErrorText if event text cannot be parsed or if a
parsing result is unexpected.
Chilkat.WebSocket:
ServerSentEvent does not manage a WebSocket connection or parse
WebSocket frames. Instead, it can be used after Chilkat.WebSocket
receives a text message whose payload is formatted as a Server-Sent Event.
Read the WebSocket text frame, pass the event text to
LoadEvent, then use EventName, Data,
LastEventId, and Retry to process the event.
LoadEvent, then inspect EventName to route the
event and Data to process the payload. Use
LastEventId and Retry when the stream provides
reconnection or event-position information.
Object Creation
import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.ServerSentEvent;
try (ServerSentEvent serverSentEvent = new ServerSentEvent()) {
// ... use serverSentEvent ...
} catch (ChilkatException e) {
System.out.println(e.getMessage()); // "ServerSentEvent.someMethod failed: <reason>"
System.out.println(e.getLastErrorText()); // the full log of the failed call
}Creates the underlying native Chilkat object. The native library (chilkat2java) is loaded the first time any Chilkat2 object is created; see the README in the download for where it is looked for (-Dchilkat2.library.path, a classpath resource, or java.library.path).
Releases the native object (ServerSentEvent is AutoCloseable, so try-with-resources calls it). Calling it again does nothing; any other method or property accessor called afterwards throws IllegalStateException. An object that is never closed is freed by a background cleaner once it becomes unreachable, but the garbage collector does not see native memory, so closing is the normal path. Objects returned by methods are owned by the caller too.
Returns true once close() has been called.
Errors
A method that fails throws ChilkatException, an unchecked exception carrying getClassName(), getMethodName(), getReason() (one line, also in the message) and getLastErrorText() (the full log, captured at the moment of the failure). The object remains usable. Methods that look something up and find nothing return null instead of throwing (each such method says so), and methods that answer a question (hasMember, isUnlocked, ...) return a plain boolean. Property accessors do not throw for Chilkat reasons.
A null string or object argument throws NullPointerException naming the parameter (except where a method documents that null is accepted), and a string containing U+0000 throws IllegalArgumentException.
Use an object from one thread at a time; it may be handed from one thread to another. The one cross-thread operation is setting setAbortCurrent(true) on an object that is busy in another thread (on the classes that have AbortCurrent). Unlocking: call new Global().unlockBundle("...") once at startup.
Properties
Data
String getData()
The data for the server-side event. (If the data field was empty, then this will be empty.)
DebugLogFilePath
String getDebugLogFilePath()
void setDebugLogFilePath(String value)
If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. This logging helps identify the context and history of Chilkat calls leading up to any crash or hang, aiding in debugging.
Enabling the VerboseLogging property provides more detailed information. This property is mainly used for debugging rare instances where a Chilkat method call causes a hang or crash, which should generally not happen.
Possible causes of hangs include:
- A timeout property set to 0, indicating an infinite timeout.
- A hang occurring within an event callback in the application code.
- An internal bug in the Chilkat code causing the hang.
EventName
String getEventName()
The name of the server-side event. (If the event field was not present, then this will be empty.)
LastErrorHtml
String getLastErrorHtml()
Provides HTML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
topLastErrorText
String getLastErrorText()
Provides plain text information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
LastErrorXml
String getLastErrorXml()
Provides XML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
topLastEventId
String getLastEventId()
The content of the id field, if present.
LastMethodSuccess
boolean getLastMethodSuccess()
void setLastMethodSuccess(boolean value)
Indicates the success or failure of the most recent method call: true means success, false means failure. This property remains unchanged by property setters or getters. This method is present to address challenges in checking for null or Nothing returns in certain programming languages. Note: This property does not apply to methods that return integer values or to boolean-returning methods where the boolean does not indicate success or failure.
Retry
int getRetry()
The integer value of the retry field, if it exists; otherwise, 0.
VerboseLogging
boolean getVerboseLogging()
void setVerboseLogging(boolean value)
If set to true, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is false. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.
Version
String getVersion()
Methods
LoadEvent
Loads the multi-line event text into this object. For example, the eventText for a Firebase event might look like this:
event: put
data: {"path": "/c", "data": {"foo": true, "bar": false}}
Throws ChilkatException on failure; e.getLastErrorText() (or the object's getLastErrorText()) explains why, and the object remains usable.