API reference

Generated Javadocs are the canonical symbol-level reference for constructors, methods, record components, implemented interfaces, and declared exceptions. These links use javadoc.io's latest alias; select a concrete version there when matching a pinned dependency.

Module Javadocs

Module Published Javadocs Primary packages
modbus Core Javadocs com.digitalpetri.modbus, .client, .server, .pdu, .exceptions, .server.authz
modbus-tcp TCP Javadocs com.digitalpetri.modbus.tcp, .tcp.client, .tcp.server, .tcp.security
modbus-serial Serial Javadocs com.digitalpetri.modbus.serial, .serial.client, .serial.server

Client API

API Javadocs Use
ModbusClient Class Lifecycle and typed synchronous/asynchronous operations
ModbusTcpClient Class MBAP correlation and raw TCP PDU operations
ModbusRtuClient Class RTU framing, CRC, and broadcasts
ModbusClientConfig Record Request timeout, scheduler, and serializers

See Client and server behavior and Client operations for cross-cutting semantics not usefully repeated on every method.

Server API

API Javadocs Use
ModbusServer Interface Server lifecycle and service replacement
ModbusTcpServer Class Modbus TCP decode/dispatch/encode path
ModbusRtuServer Class Modbus RTU decode/dispatch/encode path
ModbusServices Interface Typed service operations and range helpers
ProcessImage Class In-memory data areas and transactions
ReadOnlyModbusServices Class Process-image reads
ReadWriteModbusServices Class Process-image reads and writes
Authorization (AuthzModbusServices, AuthzHandler) Package Certificate-derived authorization around service calls

PDU API

The PDU package contains request and response records for the ten default typed function codes. Use Function codes and PDUs as the scannable function-to-type map, then use the generated record page for exact components and serializer methods.

ModbusPduSerializer and its default implementations are documented in the core Javadocs.

Transport and security API

Area Javadocs
TCP client transport/config NettyTcpClientTransport, NettyClientTransportConfig
RTU-over-TCP client NettyRtuClientTransport
TCP/RTU-over-TCP server config NettyServerTransportConfig
TCP server transport NettyTcpServerTransport
RTU-over-TCP server NettyRtuServerTransport
TLS helper SecurityUtil
Serial config SerialPortTransportConfig
Serial client/server SerialPortClientTransport, SerialPortServerTransport

See Transport configuration for defaults in one table.

Exceptions

The exceptions package contains the checked exception hierarchy. See Errors and exceptions for where each exception surfaces and how synchronous wrappers differ from asynchronous stages.

Build Javadocs from this checkout

mvn -pl modbus,modbus-tcp,modbus-serial -am javadoc:javadoc

Each module writes generated HTML below its target/reports/apidocs directory. A local javadoc:javadoc build uses a non-modular page layout, so its paths differ from the module-based layout of the published javadoc.io links. Generated files are build artifacts and are not part of the portable Markdown documentation tree.

Source entry points

Area Source
Client API ModbusClient.java
Server API ModbusServer.java
TCP client transports tcp/client
TCP server transports tcp/server
Serial transports serial
Integration tests modbus-tests