Migrate MCP Java SDK 0.8.1 → 2.0.0#1
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Upgrades from the pre-1.0 SDK to 2.0.0, which is a breaking API change
across transport, tool/resource registration, and content construction.
Behavior for end users is unchanged (same tools, same CSV output).
- pom.xml: replace mcp:0.8.1 with mcp-json-jackson2:2.0.0 (keeps JSON on
Jackson 2 instead of the 2.0 default of Jackson 3); pin jackson-databind
to 2.18.3
- Program: ServerMcpTransport/StdioServerTransport(ObjectMapper) ->
McpServerTransportProvider/StdioServerTransportProvider(McpJsonMapper via
JacksonMcpJsonMapper); register tools/resources by collecting
Sync{Tool,Resource}Specification lists into .tools()/.resources()
- Tools: ITool.register(spec) -> specification() returning a
SyncToolSpecification (Tool.builder + callHandler(exchange, request));
CallToolResult.builder(); simple TextContent(text)
- Resource: SyncResourceRegistration -> SyncResourceSpecification;
Resource.builder(uri, name); read handler takes (exchange, request)
- JsonSchemaBuilder: add buildMap() (Tool.inputSchema is now Map);
build() delegates to it
- Tests: add a buildMap() assertion (12 tests total)
Verified with mvn clean test and a live stdio JSON-RPC round-trip
(initialize, tools/list, tools/call, resources/list, resources/read)
against the CData CSV JDBC driver.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Summary
Upgrades the MCP Java SDK from the pre-1.0 0.8.1 to 2.0.0. This is an API-breaking jump across transport, tool/resource registration, and content construction — but end-user behavior is unchanged: same three tools, same CSV output, resources still opt-in via the
Tablesproperty.Key decisions
mcp:2.0.0bundle pulls Jackson 3. To avoid rewriting our own Jackson usage (JsonSchemaBuilder, tests), we depend onmcp-json-jackson2:2.0.0and wire the transport withJacksonMcpJsonMapper(new ObjectMapper()). Verifiedmvn dependency:treeresolves Jackson 2 only — no Jackson 3.Changes
mcp:0.8.1→mcp-json-jackson2:2.0.0; pinjackson-databind2.18.3.ServerMcpTransport/StdioServerTransport(ObjectMapper)→McpServerTransportProvider/StdioServerTransportProvider(McpJsonMapper); register viaSync{Tool,Resource}Specificationlists passed to.tools()/.resources().ITool+ 3 impls) —register(spec)→specification()returning aSyncToolSpecification(Tool.builder()+callHandler((exchange, request) -> ...)); results viaCallToolResult.builder();TextContent(roles, priority, text)→TextContent(text).SyncResourceRegistration→SyncResourceSpecification;Resource.builder(uri, name); read handler takes(exchange, request).buildMap()(Tool.inputSchemais now aMap);build()delegates to it.buildMap()assertion.Verification
mvn clean test— 12 tests pass.initialize(serverInfo honorsServerName/ServerVersion),tools/list(3 tools, correct schemas),tools/call csv_run_query(correct CSV,isError=false),resources/list+resources/read(column metadata). Zero errors — coverage the old code never had.Notes / risks checked
$schemapasses 2.0's default tool-input validation (non-2020-12 dialects are accepted without meta-validation).Tablesis set — unchanged from 0.8.1.🤖 Generated with Claude Code