Add boot42-rc1-checklist module: Spring Boot 4.2.0-RC1 upgrade checklist run against RC1 and 4.1.2

boot42-rc1-checklist/README.md

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+# boot42-rc1-checklist
+
+Companion module for the ankurm.com article *Spring Framework 7.1 and Spring Boot 4.2: What's Coming and How to Prepare*.
+Everything runs against **Spring Boot 4.2.0-RC1** (Spring Framework 7.1.0-RC1; a release candidate, **not GA**) and, for the before/after comparison, against **4.1.2** (GA). JDK 25.
+
+| Path | What it is |
+|---|---|
+| `pom.xml` / `pom-41.xml` | the same project on 4.2.0-RC1 and on 4.1.2 (a `${revision}` parent does not resolve from a repository, hence two files) |
+| `src/test/.../DefaultValuePlaceholderTest` | `@DefaultValue` with a `${...}` placeholder: resolved on 4.2, literal text on 4.1.2 (and a startup failure for an `int`) |
+| `src/test/.../KafkaAdminBindingTest` | the new `spring.kafka.template.admin.*` / `listener.admin.*` keys: 5 of 5 bind on 4.2, 0 of 5 on 4.1.2 with no error |
+| `src/test/.../LdapEmbeddedSslTest` | embedded LDAP `ssl.enabled=true` without a bundle: fails on 4.2, starts on 4.1.2 |
+| `src/test/.../MigratorTest` | what `spring-boot-properties-migrator` prints for the relocated Tomcat keys and the removed path-matching key |
+| `src/broken/UsesRestTemplate.java` | not built; `scripts/compile-broken.sh` compiles it with `-Xlint:deprecation` and keeps the compiler's own message |
+| `output/` | every transcript quoted in the article; `./scripts/run-all.sh` regenerates them |
+
+Run: `./scripts/run-all.sh`. Not executed here (they need Docker or a registry): the new default buildpack builder and the image-based build cache.
+
+There is deliberately no `docs/` folder: the explanations live in the article.

boot42-rc1-checklist/output/01-default-value-placeholders-on-4.1.2.txt

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+# 01-default-value-placeholders  (Spring Boot 4.1.2, JDK 25)
+no demo.* properties set:      zone = ${demo.region:eu}-primary   plain = static-value
+demo.region=ap:                zone = ${demo.region:eu}-primary
+int property, placeholder default: context FAILED to start
+root cause: java.lang.NumberFormatException
+            For input string: "${demoport.number:8080}"

boot42-rc1-checklist/output/01-default-value-placeholders.txt

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+# 01-default-value-placeholders  (Spring Boot 4.2.0-RC1, JDK 25)
+no demo.* properties set:      zone = eu-primary   plain = static-value
+demo.region=ap:                zone = ap-primary
+int property, placeholder default: number = 8080

boot42-rc1-checklist/output/02-kafka-admin-binding-on-4.1.2.txt

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+# 02-kafka-admin-binding  (Spring Boot 4.1.2, JDK 25)
+properties supplied: 5
+IGNORED  spring.kafka.listener.admin.client-id
+IGNORED  spring.kafka.listener.admin.fail-fast
+IGNORED  spring.kafka.listener.await-async-results-on-stop
+IGNORED  spring.kafka.template.admin.client-id
+IGNORED  spring.kafka.template.admin.fail-fast
+bound = 0 of 5
+listener.isAwaitAsyncResultsOnStop() = no such method
+template.getAdmin()                  = no such method

boot42-rc1-checklist/output/02-kafka-admin-binding.txt

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+# 02-kafka-admin-binding  (Spring Boot 4.2.0-RC1, JDK 25)
+properties supplied: 5
+bound    spring.kafka.listener.admin.client-id
+bound    spring.kafka.listener.admin.fail-fast
+bound    spring.kafka.listener.await-async-results-on-stop
+bound    spring.kafka.template.admin.client-id
+bound    spring.kafka.template.admin.fail-fast
+bound = 5 of 5
+listener.isAwaitAsyncResultsOnStop() = true
+template.getAdmin()                  = org.springframework.boot.kafka.autoconfigure.KafkaProperties$SimpleAdmin@889d9e8
+template admin client-id = template-admin
+template admin fail-fast = true
+listener admin client-id = listener-admin
+listener admin fail-fast = true

boot42-rc1-checklist/output/03-ldap-embedded-ssl-without-bundle-on-4.1.2.txt

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+# 03-ldap-embedded-ssl-without-bundle  (Spring Boot 4.1.2, JDK 25)
+spring.ldap.embedded.ssl.enabled=true, no bundle: context STARTED
+embedded server beans: 1

boot42-rc1-checklist/output/03-ldap-embedded-ssl-without-bundle.txt

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+# 03-ldap-embedded-ssl-without-bundle  (Spring Boot 4.2.0-RC1, JDK 25)
+spring.ldap.embedded.ssl.enabled=true, no bundle: context FAILED to start
+java.lang.IllegalStateException
+SSL is enabled but no SSL bundle has been set. An SSL bundle providing the server's certificate and private key is required for LDAPS

boot42-rc1-checklist/output/04-properties-migrator-report-on-4.1.2.txt

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+# 04-properties-migrator-report  (Spring Boot 4.1.2, JDK 25)

boot42-rc1-checklist/output/04-properties-migrator-report.txt

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+# 04-properties-migrator-report  (Spring Boot 4.2.0-RC1, JDK 25)
+The use of configuration keys that have been renamed was found in the environment:
+Property source 'defaultProperties':
+Key: server.tomcat.additional-tld-skip-patterns
+Replacement: server.tomcat.servlet.additional-tld-skip-patterns
+Key: server.tomcat.redirect-context-root
+Replacement: server.tomcat.servlet.redirect-context-root
+Key: server.tomcat.use-relative-redirects
+Replacement: server.tomcat.servlet.use-relative-redirects
+The use of configuration keys that are no longer supported was found in the environment:
+Property source 'defaultProperties':
+Key: spring.mvc.pathmatch.matching-strategy
+Reason: Path matching is no longer configurable

boot42-rc1-checklist/output/05-resttemplate-compiler-warnings-on-4.1.2.txt

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+# 05-resttemplate-compiler-warnings  (Spring Boot 4.1.2, JDK 25.0.5)
+$ javac -Xlint:deprecation -cp <module classpath> -d target/broken src/broken/UsesRestTemplate.java
+exit: 0

boot42-rc1-checklist/output/05-resttemplate-compiler-warnings.txt

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+# 05-resttemplate-compiler-warnings  (Spring Boot 4.2.0-RC1, JDK 25.0.5)
+$ javac -Xlint:deprecation -cp <module classpath> -d target/broken src/broken/UsesRestTemplate.java
+src/broken/UsesRestTemplate.java:11: warning: [removal] RestTemplateBuilder in org.springframework.boot.restclient has been deprecated and marked for removal
+	public String fetch(RestTemplateBuilder builder) {
+	                    ^
+src/broken/UsesRestTemplate.java:12: warning: [removal] RestTemplate in org.springframework.web.client has been deprecated and marked for removal
+		RestTemplate rest = builder.build();
+		^
+2 warnings
+exit: 0

boot42-rc1-checklist/pom-41.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <parent>
+    <groupId>org.springframework.boot</groupId>
+    <artifactId>spring-boot-starter-parent</artifactId>
+    <version>4.1.2</version>
+    <relativePath/>
+  </parent>
+
+  <groupId>com.ankurm</groupId>
+  <artifactId>boot42-rc1-checklist</artifactId>
+  <version>1.0.0</version>
+  <name>boot42-rc1-checklist</name>
+  <description>Spring Boot 4.2.0-RC1 upgrade checklist: each claim run against 4.2.0-RC1 and 4.1.2</description>
+
+  <properties>
+    <java.version>25</java.version>
+    <boot.label>4.1.2</boot.label>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-starter-webmvc</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-starter-restclient</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-starter-kafka</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-starter-ldap</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>com.unboundid</groupId>
+      <artifactId>unboundid-ldapsdk</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-properties-migrator</artifactId>
+      <scope>runtime</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-starter-test</artifactId>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <artifactId>maven-surefire-plugin</artifactId>
+        <configuration>
+          <systemPropertyVariables>
+            <boot.label>${boot.label}</boot.label>
+          </systemPropertyVariables>
+        </configuration>
+      </plugin>
+      <plugin>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-maven-plugin</artifactId>
+      </plugin>
+    </plugins>
+  </build>
+</project>

boot42-rc1-checklist/pom.xml

@@ -0,0 +1,74 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <parent>
+    <groupId>org.springframework.boot</groupId>
+    <artifactId>spring-boot-starter-parent</artifactId>
+    <version>4.2.0-RC1</version>
+    <relativePath/>
+  </parent>
+
+  <groupId>com.ankurm</groupId>
+  <artifactId>boot42-rc1-checklist</artifactId>
+  <version>1.0.0</version>
+  <name>boot42-rc1-checklist</name>
+  <description>Spring Boot 4.2.0-RC1 upgrade checklist: each claim run against 4.2.0-RC1 and 4.1.2</description>
+
+  <properties>
+    <java.version>25</java.version>
+    <boot.label>4.2.0-RC1</boot.label>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-starter-webmvc</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-starter-restclient</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-starter-kafka</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-starter-ldap</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>com.unboundid</groupId>
+      <artifactId>unboundid-ldapsdk</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-properties-migrator</artifactId>
+      <scope>runtime</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-starter-test</artifactId>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <artifactId>maven-surefire-plugin</artifactId>
+        <configuration>
+          <systemPropertyVariables>
+            <boot.label>${boot.label}</boot.label>
+          </systemPropertyVariables>
+        </configuration>
+      </plugin>
+      <plugin>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-maven-plugin</artifactId>
+      </plugin>
+    </plugins>
+  </build>
+</project>

boot42-rc1-checklist/scripts/compile-broken.sh

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+#!/usr/bin/env bash
+# Compiles src/broken/UsesRestTemplate.java with -Xlint:deprecation against the module classpath
+# of the given pom (default pom.xml = 4.2.0-RC1; pass pom-41.xml for the 4.1.2 baseline) and
+# stores the compiler's own message in output/05-resttemplate-compiler-warnings[-on-4.1.2].txt.
+set -u
+cd "$(dirname "$0")/.."
+POM="${1:-pom.xml}"
+LABEL=$(grep -m1 '<boot.label>' "$POM" | sed -E 's/.*<boot.label>(.*)<\/boot.label>.*/\1/')
+SUFFIX=""; [[ "$LABEL" == 4.2* ]] || SUFFIX="-on-$LABEL"
+OUT="output/05-resttemplate-compiler-warnings$SUFFIX.txt"
+mvn -B -q -f "$POM" dependency:build-classpath -Dmdep.outputFile=target/cp.txt >/dev/null 2>&1
+rm -rf target/broken && mkdir -p target/broken
+{
+  echo "# 05-resttemplate-compiler-warnings  (Spring Boot $LABEL, JDK $(javac -version 2>&1 | grep -v Picked | awk '{print $2}'))"
+  echo '$ javac -Xlint:deprecation -cp <module classpath> -d target/broken src/broken/UsesRestTemplate.java'
+  javac -Xlint:deprecation -cp "$(cat target/cp.txt)" -d target/broken src/broken/UsesRestTemplate.java 2>&1 \
+    | grep -v '^Picked up' | sed -e "s#^$(pwd)/##"
+  echo "exit: ${PIPESTATUS[0]}"
+} > "$OUT"
+cat "$OUT"

boot42-rc1-checklist/scripts/run-all.sh

@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+# Regenerates every file in output/ on Spring Boot 4.2.0-RC1 and on the 4.1.2 baseline.
+# Needs JDK 25 and Maven 3.9 on PATH.
+set -euo pipefail
+cd "$(dirname "$0")/.."
+mvn -B -q test
+mvn -B -q -f pom-41.xml test
+scripts/compile-broken.sh pom.xml >/dev/null
+scripts/compile-broken.sh pom-41.xml >/dev/null
+echo "done: $(ls output | wc -l) files in output/"

boot42-rc1-checklist/src/broken/UsesRestTemplate.java

@@ -0,0 +1,15 @@
+import org.springframework.web.client.RestTemplate;
+import org.springframework.boot.restclient.RestTemplateBuilder;
+
+/**
+ * Not part of the build. scripts/compile-broken.sh compiles it with -Xlint:deprecation and
+ * commits the compiler's own message. RestTemplate and the Boot builder around it are
+ * deprecated in Spring Framework 7.1 / Spring Boot 4.2.
+ */
+public class UsesRestTemplate {
+
+	public String fetch(RestTemplateBuilder builder) {
+		RestTemplate rest = builder.build();
+		return rest.getForObject("http://localhost:8080/ping", String.class);
+	}
+}

boot42-rc1-checklist/src/main/java/com/ankurm/rc1/DemoPort.java

@@ -0,0 +1,12 @@
+package com.ankurm.rc1;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.boot.context.properties.bind.DefaultValue;
+
+/**
+ * A non-String property with a placeholder default. On 4.1.x the literal text
+ * {@code ${demo.port:8080}} cannot be converted to int, so the context fails to start.
+ */
+@ConfigurationProperties("demoport")
+public record DemoPort(@DefaultValue("${demoport.number:8080}") int number) {
+}

boot42-rc1-checklist/src/main/java/com/ankurm/rc1/DemoProperties.java

@@ -0,0 +1,16 @@
+package com.ankurm.rc1;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.boot.context.properties.bind.DefaultValue;
+
+/**
+ * Constructor-bound properties whose defaults contain placeholders.
+ *
+ * <p>Spring Boot 4.2.0-M2 made {@code @DefaultValue} resolve property placeholders during
+ * binding. On 4.1.x the same annotation value is taken literally.
+ */
+@ConfigurationProperties("demo")
+public record DemoProperties(
+		@DefaultValue("${demo.region:eu}-primary") String zone,
+		@DefaultValue("static-value") String plain) {
+}

boot42-rc1-checklist/src/main/java/com/ankurm/rc1/Rc1ChecklistApplication.java

@@ -0,0 +1,14 @@
+package com.ankurm.rc1;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.context.properties.ConfigurationPropertiesScan;
+
+@SpringBootApplication
+@ConfigurationPropertiesScan
+public class Rc1ChecklistApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(Rc1ChecklistApplication.class, args);
+	}
+}

boot42-rc1-checklist/src/test/java/com/ankurm/rc1/DefaultValuePlaceholderTest.java

@@ -0,0 +1,68 @@
+package com.ankurm.rc1;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.boot.test.context.runner.ApplicationContextRunner;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class DefaultValuePlaceholderTest {
+
+	@EnableConfigurationProperties(DemoProperties.class)
+	static class StringConfig {
+	}
+
+	@EnableConfigurationProperties(DemoPort.class)
+	static class PortConfig {
+	}
+
+	@Test
+	void placeholderInDefaultValue() {
+		Transcript t = new Transcript("01-default-value-placeholders");
+		new ApplicationContextRunner().withUserConfiguration(StringConfig.class).run(ctx -> {
+			DemoProperties p = ctx.getBean(DemoProperties.class);
+			t.line("no demo.* properties set:      zone = " + p.zone() + "   plain = " + p.plain());
+			if (Transcript.is42()) {
+				assertThat(p.zone()).isEqualTo("eu-primary");
+			}
+			else {
+				assertThat(p.zone()).isEqualTo("${demo.region:eu}-primary");
+			}
+		});
+		new ApplicationContextRunner().withUserConfiguration(StringConfig.class)
+			.withPropertyValues("demo.region=ap")
+			.run(ctx -> {
+				DemoProperties p = ctx.getBean(DemoProperties.class);
+				t.line("demo.region=ap:                zone = " + p.zone());
+				if (Transcript.is42()) {
+					assertThat(p.zone()).isEqualTo("ap-primary");
+				}
+				else {
+					assertThat(p.zone()).isEqualTo("${demo.region:eu}-primary");
+				}
+			});
+		new ApplicationContextRunner().withUserConfiguration(PortConfig.class).run(ctx -> {
+			if (Transcript.is42()) {
+				assertThat(ctx).hasNotFailed();
+				t.line("int property, placeholder default: number = " + ctx.getBean(DemoPort.class).number());
+				assertThat(ctx.getBean(DemoPort.class).number()).isEqualTo(8080);
+			}
+			else {
+				assertThat(ctx).hasFailed();
+				Throwable root = rootCause(ctx.getStartupFailure());
+				t.line("int property, placeholder default: context FAILED to start");
+				t.line("root cause: " + root.getClass().getName());
+				t.line("            " + root.getMessage());
+			}
+		});
+		t.write();
+	}
+
+	private static Throwable rootCause(Throwable ex) {
+		Throwable t = ex;
+		while (t.getCause() != null) {
+			t = t.getCause();
+		}
+		return t;
+	}
+}

boot42-rc1-checklist/src/test/java/com/ankurm/rc1/KafkaAdminBindingTest.java

@@ -0,0 +1,98 @@
+package com.ankurm.rc1;
+
+import java.lang.reflect.Method;
+import java.util.Map;
+import java.util.Set;
+import java.util.TreeSet;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.context.properties.bind.BindContext;
+import org.springframework.boot.context.properties.bind.BindHandler;
+import org.springframework.boot.context.properties.bind.Bindable;
+import org.springframework.boot.context.properties.bind.Binder;
+import org.springframework.boot.context.properties.source.ConfigurationPropertyName;
+import org.springframework.boot.context.properties.source.MapConfigurationPropertySource;
+import org.springframework.boot.kafka.autoconfigure.KafkaProperties;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Binds the new Kafka admin properties and records which of the five keys the binder actually
+ * consumed. On 4.2 all five bind. On 4.1.2 Boot does not complain about the unknown keys; they
+ * are simply never read, which is the failure mode worth knowing about.
+ */
+class KafkaAdminBindingTest {
+
+	private static final Map<String, String> PROPS = Map.of(
+			"spring.kafka.template.admin.client-id", "template-admin",
+			"spring.kafka.template.admin.fail-fast", "true",
+			"spring.kafka.listener.admin.client-id", "listener-admin",
+			"spring.kafka.listener.admin.fail-fast", "true",
+			"spring.kafka.listener.await-async-results-on-stop", "true");
+
+	@Test
+	void adminPropertiesBind() throws Exception {
+		Transcript t = new Transcript("02-kafka-admin-binding");
+		Set<String> consumed = new TreeSet<>();
+		BindHandler recorder = new BindHandler() {
+			@Override
+			public Object onSuccess(ConfigurationPropertyName name, Bindable<?> target, BindContext context,
+					Object result) {
+				if (context.getConfigurationProperty() != null) {
+					consumed.add(name.toString());
+				}
+				return result;
+			}
+		};
+		Binder binder = new Binder(new MapConfigurationPropertySource(PROPS));
+		KafkaProperties kp = binder.bind("spring.kafka", Bindable.of(KafkaProperties.class), recorder)
+			.orElseGet(KafkaProperties::new);
+
+		t.line("properties supplied: " + PROPS.size());
+		for (String key : new TreeSet<>(PROPS.keySet())) {
+			t.line((consumed.contains(key.substring("spring.kafka.".length())) || consumed.contains(key) ? "bound    " : "IGNORED  ")
+					+ key);
+		}
+		long bound = PROPS.keySet().stream()
+			.filter(k -> consumed.contains(k.substring("spring.kafka.".length())) || consumed.contains(k))
+			.count();
+		t.line("bound = " + bound + " of " + PROPS.size());
+
+		Object listener = call(kp, "getListener");
+		Object template = call(kp, "getTemplate");
+		t.line("listener.isAwaitAsyncResultsOnStop() = " + callOrAbsent(listener, "isAwaitAsyncResultsOnStop"));
+		t.line("template.getAdmin()                  = " + callOrAbsent(template, "getAdmin"));
+		if (Transcript.is42()) {
+			assertThat(bound).isEqualTo(5);
+			Object tplAdmin = call(template, "getAdmin");
+			Object lsnAdmin = call(listener, "getAdmin");
+			t.line("template admin client-id = " + call(tplAdmin, "getClientId"));
+			t.line("template admin fail-fast = " + call(tplAdmin, "isFailFast"));
+			t.line("listener admin client-id = " + call(lsnAdmin, "getClientId"));
+			t.line("listener admin fail-fast = " + call(lsnAdmin, "isFailFast"));
+			assertThat(call(tplAdmin, "getClientId")).isEqualTo("template-admin");
+			assertThat(call(lsnAdmin, "isFailFast")).isEqualTo(true);
+		}
+		else {
+			assertThat(bound).isZero();
+		}
+		t.write();
+	}
+
+	private static Object call(Object target, String method) throws Exception {
+		Method m = target.getClass().getMethod(method);
+		return m.invoke(target);
+	}
+
+	private static String callOrAbsent(Object target, String method) {
+		try {
+			return String.valueOf(call(target, method));
+		}
+		catch (NoSuchMethodException ex) {
+			return "no such method";
+		}
+		catch (Exception ex) {
+			return ex.toString();
+		}
+	}
+}

boot42-rc1-checklist/src/test/java/com/ankurm/rc1/LdapEmbeddedSslTest.java

@@ -0,0 +1,44 @@
+package com.ankurm.rc1;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.autoconfigure.AutoConfigurations;
+import org.springframework.boot.ldap.autoconfigure.embedded.EmbeddedLdapAutoConfiguration;
+import org.springframework.boot.test.context.runner.ApplicationContextRunner;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * 4.2.0-M2: spring.ldap.embedded.ssl.enabled=true without spring.ldap.embedded.ssl.bundle now
+ * fails at startup instead of quietly starting a plain-text listener.
+ */
+class LdapEmbeddedSslTest {
+
+	@Test
+	void sslWithoutBundle() {
+		Transcript t = new Transcript("03-ldap-embedded-ssl-without-bundle");
+		new ApplicationContextRunner()
+			.withConfiguration(AutoConfigurations.of(EmbeddedLdapAutoConfiguration.class))
+			.withPropertyValues("spring.ldap.embedded.base-dn=dc=example,dc=org",
+					"spring.ldap.embedded.port=0",
+					"spring.ldap.embedded.ssl.enabled=true")
+			.run(ctx -> {
+				if (Transcript.is42()) {
+					assertThat(ctx).hasFailed();
+					Throwable root = ctx.getStartupFailure();
+					while (root.getCause() != null) {
+						root = root.getCause();
+					}
+					t.line("spring.ldap.embedded.ssl.enabled=true, no bundle: context FAILED to start");
+					t.line(root.getClass().getName());
+					t.line(root.getMessage());
+				}
+				else {
+					assertThat(ctx).hasNotFailed();
+					t.line("spring.ldap.embedded.ssl.enabled=true, no bundle: context STARTED");
+					t.line("embedded server beans: "
+							+ ctx.getBeanNamesForType(com.unboundid.ldap.listener.InMemoryDirectoryServer.class).length);
+				}
+			});
+		t.write();
+	}
+}

boot42-rc1-checklist/src/test/java/com/ankurm/rc1/MigratorTest.java

@@ -0,0 +1,54 @@
+package com.ankurm.rc1;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.WebApplicationType;
+import org.springframework.boot.test.system.CapturedOutput;
+import org.springframework.boot.test.system.OutputCaptureExtension;
+import org.springframework.context.annotation.Configuration;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Starts an empty application with the property keys 4.2 relocated or deprecated and captures
+ * what spring-boot-properties-migrator prints. The keys come from the 4.2.0-M2 configuration
+ * changelog.
+ */
+@ExtendWith(OutputCaptureExtension.class)
+class MigratorTest {
+
+	@Configuration(proxyBeanMethods = false)
+	static class Empty {
+	}
+
+	@Test
+	void migratorReport(CapturedOutput output) {
+		Transcript t = new Transcript("04-properties-migrator-report");
+		SpringApplication app = new SpringApplication(Empty.class);
+		app.setWebApplicationType(WebApplicationType.NONE);
+		app.setDefaultProperties(java.util.Map.of(
+				"server.tomcat.use-relative-redirects", "false",
+				"server.tomcat.redirect-context-root", "false",
+				"server.tomcat.additional-tld-skip-patterns", "*.jar",
+				"spring.mvc.pathmatch.matching-strategy", "path_pattern_parser",
+				"management.metrics.observations.ignored-meters", "http.server.requests"));
+		app.run().close();
+		boolean any = false;
+		for (String line : output.getAll().split("\n")) {
+			String s = line.strip();
+			if (s.startsWith("Property source") || s.startsWith("Key:") || s.startsWith("Reason:")
+					|| s.startsWith("Replacement:") || s.contains("configuration keys")
+					|| s.contains("have been renamed") || s.contains("deprecated") && s.contains("configuration")
+					|| s.contains("no longer supported") || s.contains("been removed")) {
+				t.line(s);
+				any = true;
+			}
+		}
+		if (Transcript.is42()) {
+			assertThat(output.getAll()).contains("server.tomcat.servlet.use-relative-redirects");
+			assertThat(any).isTrue();
+		}
+		t.write();
+	}
+}

boot42-rc1-checklist/src/test/java/com/ankurm/rc1/Transcript.java

@@ -0,0 +1,45 @@
+package com.ankurm.rc1;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Collects lines and writes output/NN-name.txt (or NN-name-on-4.1.2.txt when run against the
+ * 4.1 baseline). The test asserts the same values it writes, so every figure quoted in the
+ * article is an assertion that fails the build when it stops being true.
+ */
+final class Transcript {
+
+	static final String LABEL = System.getProperty("boot.label", "4.2.0-RC1");
+
+	static boolean is42() {
+		return LABEL.startsWith("4.2");
+	}
+
+	private final List<String> lines = new ArrayList<>();
+	private final Path file;
+
+	Transcript(String name) {
+		String suffix = is42() ? "" : "-on-" + LABEL;
+		this.file = Path.of("output", name + suffix + ".txt");
+		line("# " + name + "  (Spring Boot " + LABEL + ", JDK " + Runtime.version().feature() + ")");
+	}
+
+	Transcript line(String s) {
+		lines.add(s);
+		return this;
+	}
+
+	void write() {
+		try {
+			Files.createDirectories(file.getParent());
+			Files.write(file, lines);
+		}
+		catch (IOException ex) {
+			throw new IllegalStateException(ex);
+		}
+	}
+}