Document the java info contribution

Closes gh-45566

Author: philwebb

spring-boot-project/spring-boot-actuator-autoconfigure/src/docs/antora/modules/api/pages/rest/actuator/info.adoc

@@ -66,3 +66,13 @@ The following table describes the structure of the `process` section of the resp
 
 [cols="2,1,3"]
 include::partial$rest/actuator/info/response-fields-beneath-process.adoc[]
+
+
+
+[[info.retrieving.response-structure.java]]
+==== Java Response Structure
+
+The following table describes the structure of the `java` section of the response:
+
+[cols="2,1,3"]
+include::partial$rest/actuator/info/response-fields-beneath-java.adoc[]

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/info/InfoEndpointDocumentationTests.java

@@ -27,6 +27,7 @@
 import org.springframework.boot.actuate.info.GitInfoContributor;
 import org.springframework.boot.actuate.info.InfoContributor;
 import org.springframework.boot.actuate.info.InfoEndpoint;
+import org.springframework.boot.actuate.info.JavaInfoContributor;
 import org.springframework.boot.actuate.info.OsInfoContributor;
 import org.springframework.boot.actuate.info.ProcessInfoContributor;
 import org.springframework.boot.info.BuildProperties;
@@ -55,7 +56,8 @@ class InfoEndpointDocumentationTests extends MockMvcEndpointDocumentationTests {
 	void info() throws Exception {
 		this.mockMvc.perform(get("/actuator/info"))
 			.andExpect(status().isOk())
-			.andDo(MockMvcRestDocumentation.document("info", gitInfo(), buildInfo(), osInfo(), processInfo()));
+			.andDo(MockMvcRestDocumentation.document("info", gitInfo(), buildInfo(), osInfo(), processInfo(),
+					javaInfo()));
 	}
 
 	private ResponseFieldsSnippet gitInfo() {
@@ -100,6 +102,35 @@ private ResponseFieldsSnippet processInfo() {
 					.type(JsonFieldType.NUMBER));
 	}
 
+	private ResponseFieldsSnippet javaInfo() {
+		return responseFields(beneathPath("java"),
+				fieldWithPath("version").description("Java version, if available.")
+					.type(JsonFieldType.STRING)
+					.optional(),
+				fieldWithPath("vendor").description("Vendor details."),
+				fieldWithPath("vendor.name").description("Vendor name, if available.")
+					.type(JsonFieldType.STRING)
+					.optional(),
+				fieldWithPath("vendor.version").description("Vendor version, if available.")
+					.type(JsonFieldType.STRING)
+					.optional(),
+				fieldWithPath("runtime").description("Runtime details."),
+				fieldWithPath("runtime.name").description("Runtime name, if available.")
+					.type(JsonFieldType.STRING)
+					.optional(),
+				fieldWithPath("runtime.version").description("Runtime version, if available.")
+					.type(JsonFieldType.STRING)
+					.optional(),
+				fieldWithPath("jvm").description("JVM details."),
+				fieldWithPath("jvm.name").description("JVM name, if available.").type(JsonFieldType.STRING).optional(),
+				fieldWithPath("jvm.vendor").description("JVM vendor, if available.")
+					.type(JsonFieldType.STRING)
+					.optional(),
+				fieldWithPath("jvm.version").description("JVM version, if available.")
+					.type(JsonFieldType.STRING)
+					.optional());
+	}
+
 	@Configuration(proxyBeanMethods = false)
 	static class TestConfiguration {
 
@@ -139,6 +170,11 @@ ProcessInfoContributor processInfoContributor() {
 			return new ProcessInfoContributor();
 		}
 
+		@Bean
+		JavaInfoContributor javaInfoContributor() {
+			return new JavaInfoContributor();
+		}
+
 	}
 
 }