application.yml

server:
  port: 8443
  ssl:
    key-password: keypass
    key-store: classpath:local.keystore
    key-store-password: storepass

pom.xml

<?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>2.1.9.RELEASE</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>tomcat-ssl-bug</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>demo</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>keytool-maven-plugin</artifactId>
                <version>1.5</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>generateKeyPair</goal>
                        </goals>
                        <phase>generate-resources</phase>
                    </execution>
                </executions>
                <configuration>
                    <keystore>${project.basedir}/src/main/resources/local.keystore</keystore>
                    <storepass>storepass</storepass>
                    <keypass>keypass</keypass>
                    <alias>foo_alias</alias>
                    <dname>cn=localhost, ou=None, L=Dallas, ST=Texas, o=LocalCom, c=US</dname>
                    <sigalg>SHA256withRSA</sigalg>
                    <ext></ext>
                    <validity>100</validity>
                    <keyalg>RSA</keyalg>
                    <keysize>2048</keysize>
                    <skipIfExist>true</skipIfExist>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>