Claude Code v2.1.23
▝▜█████▛▘ Opus 4.5 · Claude Max
▘▘ ▝▝ ~/projects/2025/javablog.com/services
✻ Conversation compacted (ctrl+o for history)
❯ /compact
⎿ Compacted (ctrl+o to see full summary)
⎿ Read domain/pom.xml (51 lines)
⎿ Read domain/src/main/java/com/javablog/domain/blog/Comment.java (11 lines)
⎿ Read domain/src/main/java/com/javablog/domain/blog/Post.java (11 lines)
⎿ Read domain/src/main/java/com/javablog/domain/blog/CreatedAt.java (15 lines)
⎿ Read domain/src/main/java/com/javablog/domain/blog/Author.java (9 lines)
❯ alright - the domain is going to use an Uncle Bob classic "Guard" class in the com.javablog.domain package. This guard class has a static function: Guard.againstNull(Object value, String fieldName);
Instead of using an @NotNull annotation the compact constructor should be defined without parameters and refer the value, for instance in Title, to the Guard.againstNull(value, "Title.value")
implementation. If the object in againstNull is null - it should throw a ConstraintViolationException, a domain defined class that extends RuntimeException and prints a pretty message based upon the
"Title.value" helper and the context of the throwing function. write the Guard, apply it to Title, update the test to use assertj to assert the exception is thrown with the appropriate exception
instance and message.
⏺ I'll create the Guard class and ConstraintViolationException, update Title, and fix the test. Let me first check the current state of TitleTest.
⏺ Searched for 1 pattern, read 1 file (ctrl+o to expand)
⏺ TitleTest doesn't exist yet. Let me check if AssertJ is in the dependencies.
⏺ Read 1 file (ctrl+o to expand)
⏺ I need to add AssertJ. Let me create all the files.
⏺ Write(domain/src/main/java/com/javablog/domain/ConstraintViolationException.java)
⎿ Wrote 9 lines to domain/src/main/java/com/javablog/domain/ConstraintViolationException.java
package com.javablog.domain;
public class ConstraintViolationException extends RuntimeException {
public ConstraintViolationException(String message) {
super(message);
}
}
⏺ Write(domain/src/main/java/com/javablog/domain/Guard.java)
⎿ Wrote 14 lines to domain/src/main/java/com/javablog/domain/Guard.java
package com.javablog.domain;
public final class Guard {
private Guard() {
}
public static void againstNull(Object value, String fieldName) {
if (value == null) {
throw new ConstraintViolationException(fieldName + " must not be null");
… +4 lines (ctrl+o to expand)
⏺ Update(domain/src/main/java/com/javablog/domain/blog/Title.java)
⎿ Added 6 lines
1 package com.javablog.domain.blog;
2
3 +import com.javablog.domain.Guard;
4 +
5 public record Title(String value) {
6
7 + public Title {
8 + Guard.againstNull(value, "Title.value");
9 + }
10 +
11 public static Title of(String value) {
12 return new Title(value);
13 }
⏺ Update(domain/pom.xml)
⎿ Added 5 lines
22 junit-jupiter-params
23 test
24
25 +
26 + org.assertj
27 + assertj-core
28 + test
29 +
30
31
32
⏺ Write(domain/src/test/java/com/javablog/domain/blog/TitleTest.java)
⎿ Wrote 17 lines to domain/src/test/java/com/javablog/domain/blog/TitleTest.java
package com.javablog.domain.blog;
import com.javablog.domain.ConstraintViolationException;
import org.junit.jupiter.api.Test;
import static org.assertj.core.api.Assertions.assertThatThrownBy;
class TitleTest {
@Test
… +7 lines (ctrl+o to expand)
⎿ Found 2 new diagnostic issues in 1 file (ctrl+o to expand)
⏺ Created:
- Guard.java - static againstNull(Object, String) method
- ConstraintViolationException.java - extends RuntimeException
- Updated Title.java with compact constructor calling Guard
- Added AssertJ dependency to pom.xml
- TitleTest.java using AssertJ assertions
Please run mvn test -pl domain to verify.
✻ Crunched for 38s
❯ its too early to execute the maven, the other tests need to be cleaned out first. change the other domain objects to use the Guard where appropriate. Add an additional Guard.againstEmpty. And
Guard.againstInvalidLength. that should encompass all of the validations we were using. Update the domain classes to use these guards where we were using Annotations before. Remove the static of()
and other static constructors I didn't ask for.
⏺ Let me read all the domain classes to see the current state and what validations are needed.
⏺ Searched for 2 patterns, read 7 files (ctrl+o to expand)
⏺ Let me read the existing tests to see what validations were expected.
⏺ Read 5 files (ctrl+o to expand)
⏺ Let me check for CommentTest and AuthorTest.
⏺ Searched for 2 patterns (ctrl+o to expand)
⏺ Now I understand the validation rules from the tests:
- PostId/CommentId: value not null
- Title/Slug/Author: not blank (null, empty, whitespace all invalid)
- Slug: also max length 255
- Content: not empty (null or empty invalid)
- CreatedAt: value not null
Let me update everything.
⏺ Write(domain/src/main/java/com/javablog/domain/Guard.java)
⎿ Added 20 lines
10 throw new ConstraintViolationException(fieldName + " must not be null");
11 }
12 }
13 +
14 + public static void againstEmpty(String value, String fieldName) {
15 + againstNull(value, fieldName);
16 + if (value.isEmpty()) {
17 + throw new ConstraintViolationException(fieldName + " must not be empty");
18 + }
19 + }
20 +
21 + public static void againstBlank(String value, String fieldName) {
22 + againstNull(value, fieldName);
23 + if (value.isBlank()) {
24 + throw new ConstraintViolationException(fieldName + " must not be blank");
25 + }
26 + }
27 +
28 + public static void againstInvalidLength(String value, String fieldName, int min, int max) {
29 + if (value != null && (value.length() < min || value.length() > max)) {
30 + throw new ConstraintViolationException(fieldName + " must be between " + min + " and " + max + " characters");
31 + }
32 + }
33 }
⎿ Found 3 new diagnostic issues in 1 file (ctrl+o to expand)
⏺ Now let me update all domain classes - removing static of() methods and adding Guards.
⏺ Write(domain/src/main/java/com/javablog/domain/blog/PostId.java)
⎿ Added 6 lines, removed 4 lines
1 package com.javablog.domain.blog;
2
3 +import com.javablog.domain.Guard;
4 +
5 import java.util.UUID;
6
7 public record PostId(UUID value) {
8
9 + public PostId {
10 + Guard.againstNull(value, "PostId.value");
11 + }
12 +
13 public static PostId generate() {
14 return new PostId(UUID.randomUUID());
15 }
16 -
17 - public static PostId of(UUID value) {
18 - return new PostId(value);
19 - }
16 }
⏺ Write(domain/src/main/java/com/javablog/domain/blog/CommentId.java)
⎿ Added 6 lines, removed 4 lines
1 package com.javablog.domain.blog;
2
3 +import com.javablog.domain.Guard;
4 +
5 import java.util.UUID;
6
7 public record CommentId(UUID value) {
8
9 + public CommentId {
10 + Guard.againstNull(value, "CommentId.value");
11 + }
12 +
13 public static CommentId generate() {
14 return new CommentId(UUID.randomUUID());
15 }
16 -
17 - public static CommentId of(UUID value) {
18 - return new CommentId(value);
19 - }
16 }
⏺ Write(domain/src/main/java/com/javablog/domain/blog/Title.java)
⎿ Added 1 line, removed 5 lines
5 public record Title(String value) {
6
7 public Title {
8 - Guard.againstNull(value, "Title.value");
8 + Guard.againstBlank(value, "Title.value");
9 }
10 -
11 - public static Title of(String value) {
12 - return new Title(value);
13 - }
10 }
⏺ Write(domain/src/main/java/com/javablog/domain/blog/Slug.java)
⎿ Added 5 lines, removed 2 lines
1 package com.javablog.domain.blog;
2
3 +import com.javablog.domain.Guard;
4 +
5 public record Slug(String value) {
6
7 - public static Slug of(String value) {
8 - return new Slug(value);
7 + public Slug {
8 + Guard.againstBlank(value, "Slug.value");
9 + Guard.againstInvalidLength(value, "Slug.value", 1, 255);
10 }
11 }
⏺ Write(domain/src/main/java/com/javablog/domain/blog/Content.java)
⎿ Added 4 lines, removed 2 lines
1 package com.javablog.domain.blog;
2
3 +import com.javablog.domain.Guard;
4 +
5 public record Content(String value) {
6
7 - public static Content of(String value) {
8 - return new Content(value);
7 + public Content {
8 + Guard.againstEmpty(value, "Content.value");
9 }
10 }
⏺ Write(domain/src/main/java/com/javablog/domain/blog/Author.java)
⎿ Added 4 lines, removed 2 lines
1 package com.javablog.domain.blog;
2
3 +import com.javablog.domain.Guard;
4 +
5 public record Author(String value) {
6
7 - public static Author of(String value) {
8 - return new Author(value);
7 + public Author {
8 + Guard.againstBlank(value, "Author.value");
9 }
10 }
⏺ Write(domain/src/main/java/com/javablog/domain/blog/CreatedAt.java)
⎿ Added 6 lines, removed 4 lines
1 package com.javablog.domain.blog;
2
3 +import com.javablog.domain.Guard;
4 +
5 import java.time.LocalDateTime;
6
7 public record CreatedAt(LocalDateTime value) {
8
9 + public CreatedAt {
10 + Guard.againstNull(value, "CreatedAt.value");
11 + }
12 +
13 public static CreatedAt now() {
14 return new CreatedAt(LocalDateTime.now());
15 }
16 -
17 - public static CreatedAt of(LocalDateTime value) {
18 - return new CreatedAt(value);
19 - }
16 }
⏺ Write(domain/src/main/java/com/javablog/domain/blog/Post.java)
⎿ Added 10 lines
1 package com.javablog.domain.blog;
2
3 +import com.javablog.domain.Guard;
4 +
5 public record Post(
6 PostId id,
7 Slug slug,
...
7 Content content,
8 CreatedAt createdAt
9 ) {
10 +
11 + public Post {
12 + Guard.againstNull(id, "Post.id");
13 + Guard.againstNull(slug, "Post.slug");
14 + Guard.againstNull(title, "Post.title");
15 + Guard.againstNull(content, "Post.content");
16 + Guard.againstNull(createdAt, "Post.createdAt");
17 + }
18 }
⏺ Write(domain/src/main/java/com/javablog/domain/blog/Comment.java)
⎿ Added 10 lines
1 package com.javablog.domain.blog;
2
3 +import com.javablog.domain.Guard;
4 +
5 public record Comment(
6 CommentId id,
7 PostId postId,
...
7 Content content,
8 CreatedAt createdAt
9 ) {
10 +
11 + public Comment {
12 + Guard.againstNull(id, "Comment.id");
13 + Guard.againstNull(postId, "Comment.postId");
14 + Guard.againstNull(author, "Comment.author");
15 + Guard.againstNull(content, "Comment.content");
16 + Guard.againstNull(createdAt, "Comment.createdAt");
17 + }
18 }
⏺ Now let me update the tests to use AssertJ assertions for ConstraintViolationException. First let me check the Fixture class.
⏺ Read 1 file (ctrl+o to expand)
⏺ I need to update Fixture to use constructors directly since I removed the of() methods.
⏺ Write(domain/src/test/java/com/javablog/domain/Fixture.java)
⎿ Added 4 lines, removed 28 lines
24 }
25
26 public static Title title() {
27 - return Title.of("Test Title");
27 + return new Title("Test Title");
28 }
29
30 - public static Title title(String value) {
31 - return Title.of(value);
32 - }
33 -
30 public static Slug slug() {
31 - return Slug.of("test-slug");
31 + return new Slug("test-slug");
32 }
33
34 - public static Slug slug(String value) {
35 - return Slug.of(value);
36 - }
37 -
34 public static Content content() {
35 - return Content.of("Test content");
35 + return new Content("Test content");
36 }
37
38 - public static Content content(String value) {
39 - return Content.of(value);
40 - }
41 -
38 public static Author author() {
39 - return Author.of("Ben");
39 + return new Author("Ben");
40 }
41
42 - public static Author author(String value) {
43 - return Author.of(value);
44 - }
45 -
42 public static CreatedAt createdAt() {
43 return CreatedAt.now();
44 }
...
63 return new Post(postId(), slug(), title(), content(), createdAt());
64 }
65
66 - public static Post post(PostId id) {
67 - return new Post(id, slug(), title(), content(), createdAt());
68 - }
69 -
66 public static Comment comment() {
67 return new Comment(commentId(), postId(), author(), content(), createdAt());
68 }
69 -
70 - public static Comment comment(PostId postId) {
71 - return new Comment(commentId(), postId, author(), content(), createdAt());
72 - }
69 }
⏺ Now let me update all the tests.
⏺ Write(domain/src/test/java/com/javablog/domain/blog/PostIdTest.java)
⎿ Added 8 lines, removed 14 lines
1 package com.javablog.domain.blog;
2
3 -import jakarta.validation.Validation;
4 -import jakarta.validation.Validator;
5 -import org.junit.jupiter.params.ParameterizedTest;
6 -import org.junit.jupiter.params.provider.NullSource;
3 +import com.javablog.domain.ConstraintViolationException;
4 +import org.junit.jupiter.api.Test;
5
6 -import java.util.UUID;
6 +import static org.assertj.core.api.Assertions.assertThatThrownBy;
7
8 -import static org.junit.jupiter.api.Assertions.assertFalse;
9 -
8 class PostIdTest {
9
10 - private final Validator validator = Validation.buildDefaultValidatorFactory().getValidator();
11 -
12 - @ParameterizedTest
13 - @NullSource
14 - void validateConstraints(UUID value) {
15 - var postId = new PostId(value);
16 - assertFalse(validator.validate(postId).isEmpty());
10 + @Test
11 + void validateConstraints() {
12 + assertThatThrownBy(() -> new PostId(null))
13 + .isInstanceOf(ConstraintViolationException.class)
14 + .hasMessage("PostId.value must not be null");
15 }
16 }
⏺ Write(domain/src/test/java/com/javablog/domain/blog/TitleTest.java)
⎿ Added 15 lines, removed 6 lines
1 package com.javablog.domain.blog;
2
3 import com.javablog.domain.ConstraintViolationException;
4 -import org.junit.jupiter.api.Test;
4 +import org.junit.jupiter.params.ParameterizedTest;
5 +import org.junit.jupiter.params.provider.MethodSource;
6 +import org.junit.jupiter.params.provider.NullAndEmptySource;
7
8 +import java.util.stream.Stream;
9 +
10 import static org.assertj.core.api.Assertions.assertThatThrownBy;
11
12 class TitleTest {
13
14 - @Test
15 - void validateConstraints() {
16 - assertThatThrownBy(() -> new Title(null))
17 - .isInstanceOf(ConstraintViolationException.class)
18 - .hasMessage("Title.value must not be null");
14 + @ParameterizedTest
15 + @NullAndEmptySource
16 + @MethodSource
17 + void validateConstraints(String value) {
18 + assertThatThrownBy(() -> new Title(value))
19 + .isInstanceOf(ConstraintViolationException.class);
20 }
21 +
22 + static Stream validateConstraints() {
23 + return Stream.of(" ");
24 + }
25 }
⏺ Write(domain/src/test/java/com/javablog/domain/blog/SlugTest.java)
⎿ Added 4 lines, removed 7 lines
1 package com.javablog.domain.blog;
2
3 -import jakarta.validation.Validation;
4 -import jakarta.validation.Validator;
3 +import com.javablog.domain.ConstraintViolationException;
4 import org.junit.jupiter.params.ParameterizedTest;
5 import org.junit.jupiter.params.provider.MethodSource;
6 import org.junit.jupiter.params.provider.NullAndEmptySource;
7
8 import java.util.stream.Stream;
9
10 -import static org.junit.jupiter.api.Assertions.assertFalse;
10 +import static org.assertj.core.api.Assertions.assertThatThrownBy;
11
12 class SlugTest {
13
14 - private final Validator validator = Validation.buildDefaultValidatorFactory().getValidator();
15 -
14 @ParameterizedTest
15 @NullAndEmptySource
16 @MethodSource
17 void validateConstraints(String value) {
18 - var slug = new Slug(value);
19 - assertFalse(validator.validate(slug).isEmpty());
18 + assertThatThrownBy(() -> new Slug(value))
19 + .isInstanceOf(ConstraintViolationException.class);
20 }
21
22 static Stream validateConstraints() {
⏺ Write(domain/src/test/java/com/javablog/domain/blog/ContentTest.java)
⎿ Added 4 lines, removed 5 lines
1 package com.javablog.domain.blog;
2
3 -import jakarta.validation.Validation;
4 -import jakarta.validation.Validator;
3 +import com.javablog.domain.ConstraintViolationException;
4 import org.junit.jupiter.params.ParameterizedTest;
5 import org.junit.jupiter.params.provider.NullAndEmptySource;
6
7 -import static org.junit.jupiter.api.Assertions.assertFalse;
7 +import static org.assertj.core.api.Assertions.assertThatThrownBy;
8
9 class ContentTest {
10
11 @ParameterizedTest
12 @NullAndEmptySource
13 void validateConstraints(String value) {
14 - var content = new Content(value);
15 - assertFalse(validator.validate(content).isEmpty());
14 + assertThatThrownBy(() -> new Content(value))
15 + .isInstanceOf(ConstraintViolationException.class);
16 }
17 }
⏺ Write(domain/src/test/java/com/javablog/domain/blog/CreatedAtTest.java)
⎿ Added 8 lines, removed 14 lines
1 package com.javablog.domain.blog;
2
3 -import jakarta.validation.Validation;
4 -import jakarta.validation.Validator;
5 -import org.junit.jupiter.params.ParameterizedTest;
6 -import org.junit.jupiter.params.provider.NullSource;
3 +import com.javablog.domain.ConstraintViolationException;
4 +import org.junit.jupiter.api.Test;
5
6 -import java.time.LocalDateTime;
6 +import static org.assertj.core.api.Assertions.assertThatThrownBy;
7
8 -import static org.junit.jupiter.api.Assertions.assertFalse;
9 -
8 class CreatedAtTest {
9
10 - private final Validator validator = Validation.buildDefaultValidatorFactory().getValidator();
11 -
12 - @ParameterizedTest
13 - @NullSource
14 - void validateConstraints(LocalDateTime value) {
15 - var createdAt = new CreatedAt(value);
16 - assertFalse(validator.validate(createdAt).isEmpty());
10 + @Test
11 + void validateConstraints() {
12 + assertThatThrownBy(() -> new CreatedAt(null))
13 + .isInstanceOf(ConstraintViolationException.class)
14 + .hasMessage("CreatedAt.value must not be null");
15 }
16 }
⏺ Write(domain/src/test/java/com/javablog/domain/blog/PostTest.java)
⎿ Added 5 lines, removed 13 lines
1 package com.javablog.domain.blog;
2
3 -import jakarta.validation.Validation;
4 -import jakarta.validation.Validator;
3 +import com.javablog.domain.ConstraintViolationException;
4 import org.junit.jupiter.params.ParameterizedTest;
5 import org.junit.jupiter.params.provider.Arguments;
6 import org.junit.jupiter.params.provider.MethodSource;
...
9 import java.util.stream.Stream;
10
11 import static com.javablog.domain.Fixture.*;
12 -import static org.junit.jupiter.api.Assertions.assertFalse;
12 +import static org.assertj.core.api.Assertions.assertThatThrownBy;
13
14 class PostTest {
15
16 - private final Validator validator = Validation.buildDefaultValidatorFactory().getValidator();
17 -
16 @ParameterizedTest
17 @MethodSource
18 void validateConstraints(PostId id, Slug slug, Title title, Content content, CreatedAt createdAt) {
19 - var post = new Post(id, slug, title, content, createdAt);
20 - assertFalse(validator.validate(post).isEmpty());
19 + assertThatThrownBy(() -> new Post(id, slug, title, content, createdAt))
20 + .isInstanceOf(ConstraintViolationException.class);
21 }
22
23 static Stream validateConstraints() {
...
28 Arguments.of(postId(), null, title(), content(), createdAt()),
29 Arguments.of(postId(), slug(), null, content(), createdAt()),
30 Arguments.of(postId(), slug(), title(), null, createdAt()),
31 - Arguments.of(postId(), slug(), title(), content(), null),
32 - Arguments.of(new PostId(null), slug(), title(), content(), createdAt()),
33 - Arguments.of(postId(), new Slug(""), title(), content(), createdAt()),
34 - Arguments.of(postId(), slug(), new Title(""), content(), createdAt()),
35 - Arguments.of(postId(), slug(), title(), new Content(""), createdAt()),
36 - Arguments.of(postId(), slug(), title(), content(), new CreatedAt(null))
31 + Arguments.of(postId(), slug(), title(), content(), null)
32 );
33 }
34 }
⏺ Done. Summary of changes:
Guard.java - added methods:
- againstNull(Object, String) - null check
- againstEmpty(String, String) - null + empty check
- againstBlank(String, String) - null + blank (whitespace) check
- againstInvalidLength(String, String, int, int) - length range check
Domain records updated with Guards:
- PostId, CommentId - againstNull for UUID
- Title, Author - againstBlank
- Slug - againstBlank + againstInvalidLength(1, 255)
- Content - againstEmpty
- CreatedAt - againstNull for LocalDateTime
- Post, Comment - againstNull for all fields
Removed: All static of() methods (kept generate() for IDs, now() for CreatedAt)
Tests updated to use AssertJ assertThatThrownBy checking for ConstraintViolationException
Please run mvn test -pl domain to verify.
✻ Sautéed for 3m 11s
❯ remove the rest of the static of methods from the rest of the codebase.
⎿ Loaded adapter-persistence/CLAUDE.md
⏺ Searched for 2 patterns (ctrl+o to expand)
⏺ No remaining static of() methods found in the codebase. They've all been removed.
❯ haha - have a look at JpaBlogRepository
⏺ Read 1 file (ctrl+o to expand)
⏺ The toDomain methods are calling the now-removed of() methods. Let me fix that.
⏺ Update(adapter-persistence/src/main/java/com/javablog/adapter/persistence/blog/JpaBlogRepository.java)
⎿ Added 10 lines, removed 10 lines
43
44 private Post toDomain(PostEntity entity) {
45 return new Post(
46 - PostId.of(entity.getPostId()),
47 - Slug.of(entity.getSlug()),
48 - Title.of(entity.getTitle()),
49 - Content.of(entity.getContent()),
50 - CreatedAt.of(entity.getCreatedAt())
46 + new PostId(entity.getPostId()),
47 + new Slug(entity.getSlug()),
48 + new Title(entity.getTitle()),
49 + new Content(entity.getContent()),
50 + new CreatedAt(entity.getCreatedAt())
51 );
52 }
53
54 private Comment toDomain(CommentEntity entity) {
55 return new Comment(
56 - CommentId.of(entity.getCommentId()),
57 - PostId.of(entity.getPost().getPostId()),
58 - Author.of(entity.getAuthor()),
59 - Content.of(entity.getContent()),
60 - CreatedAt.of(entity.getCreatedAt())
56 + new CommentId(entity.getCommentId()),
57 + new PostId(entity.getPost().getPostId()),
58 + new Author(entity.getAuthor()),
59 + new Content(entity.getContent()),
60 + new CreatedAt(entity.getCreatedAt())
61 );
62 }
63 }
⏺ Let me check for any other usages I might have missed.
⏺ Searched for 1 pattern (ctrl+o to expand)
⏺ All clean - the remaining .of() calls are standard Java (Stream.of, List.of, Arguments.of), not the domain object factory methods.
❯ Instead Of the BlogRepository.listPosts() returning a list of posts it should return a Posts object which takes a Set values in its constructor. The set may be empty, but not null.
⏺ Read 1 file (ctrl+o to expand)
⏺ Write(domain/src/main/java/com/javablog/domain/blog/Posts.java)
⎿ Wrote 13 lines to domain/src/main/java/com/javablog/domain/blog/Posts.java
package com.javablog.domain.blog;
import com.javablog.domain.Guard;
import java.util.Set;
public record Posts(Set values) {
public Posts {
Guard.againstNull(values, "Posts.values");
… +3 lines (ctrl+o to expand)
⏺ Update(domain/src/main/java/com/javablog/domain/blog/BlogRepository.java)
⎿ Added 1 line, removed 1 line
4
5 public interface BlogRepository {
6
7 - List listPosts();
7 + Posts listPosts();
8
9 List listComments(Post post);
10 }
⏺ Read 1 file (ctrl+o to expand)
⎿ Found 3 new diagnostic issues in 1 file (ctrl+o to expand)
⏺ Update(adapter-persistence/src/main/java/com/javablog/adapter/persistence/blog/JpaBlogRepository.java)
⎿ Added 2 lines
8 import com.javablog.domain.CreatedAt;
9 import com.javablog.domain.blog.Post;
10 import com.javablog.domain.blog.PostId;
11 +import com.javablog.domain.blog.Posts;
12 import com.javablog.domain.Slug;
13 import com.javablog.domain.Title;
14 import jakarta.persistence.EntityManager;
...
15 import org.springframework.stereotype.Repository;
16
17 import java.util.List;
18 +import java.util.stream.Collectors;
19
20 @Repository
21 public class JpaBlogRepository implements BlogRepository {
⏺ Update(adapter-persistence/src/main/java/com/javablog/adapter/persistence/blog/JpaBlogRepository.java)
⎿ Added 3 lines, removed 3 lines
25 private EntityManager entityManager;
26
27 @Override
28 - public List listPosts() {
29 - return entityManager.createNamedQuery(PostEntity.FIND_ALL, PostEntity.class)
28 + public Posts listPosts() {
29 + return new Posts(entityManager.createNamedQuery(PostEntity.FIND_ALL, PostEntity.class)
30 .getResultList()
31 .stream()
32 .map(this::toDomain)
33 - .toList();
33 + .collect(Collectors.toSet()));
34 }
35
36 @Override
⏺ Let me check if there are any callers of listPosts() that need updating.
⏺ Searched for 1 pattern (ctrl+o to expand)
⏺ Done. Created Posts record and updated BlogRepository and JpaBlogRepository. No other callers needed updating.
✻ Sautéed for 40s
❯ apply the same pattern to Comments. use a "plural" domain object and its not allowed to have null values.
⏺ Write(domain/src/main/java/com/javablog/domain/blog/Comments.java)
⎿ Wrote 13 lines to domain/src/main/java/com/javablog/domain/blog/Comments.java
package com.javablog.domain.blog;
import com.javablog.domain.Guard;
import java.util.Set;
public record Comments(Set values) {
public Comments {
Guard.againstNull(values, "Comments.values");
… +3 lines (ctrl+o to expand)
⏺ Update(domain/src/main/java/com/javablog/domain/blog/BlogRepository.java)
⎿ Added 1 line, removed 3 lines
1 package com.javablog.domain.blog;
2
3 -import java.util.List;
4 -
3 public interface BlogRepository {
4
5 Posts listPosts();
6
7 - List listComments(Post post);
7 + Comments listComments(Post post);
8 }
⏺ Update(adapter-persistence/src/main/java/com/javablog/adapter/persistence/blog/JpaBlogRepository.java)
⎿ Added 1 line
4 import com.javablog.domain.blog.BlogRepository;
5 import com.javablog.domain.Comment;
6 import com.javablog.domain.CommentId;
7 +import com.javablog.domain.Comments;
8 import com.javablog.domain.Content;
9 import com.javablog.domain.CreatedAt;
10 import com.javablog.domain.blog.Post;
⏺ Update(adapter-persistence/src/main/java/com/javablog/adapter/persistence/blog/JpaBlogRepository.java)
⎿ Removed 1 line
16 import jakarta.persistence.PersistenceContext;
17 import org.springframework.stereotype.Repository;
18
19 -import java.util.List;
19 import java.util.stream.Collectors;
20
21 @Repository
⏺ Update(adapter-persistence/src/main/java/com/javablog/adapter/persistence/blog/JpaBlogRepository.java)
⎿ Added 3 lines, removed 3 lines
34 }
35
36 @Override
37 - public List listComments(Post post) {
38 - return entityManager.createNamedQuery(CommentEntity.FIND_BY_POST_ID, CommentEntity.class)
37 + public Comments listComments(Post post) {
38 + return new Comments(entityManager.createNamedQuery(CommentEntity.FIND_BY_POST_ID, CommentEntity.class)
39 .setParameter("postId", post.id().value())
40 .getResultList()
41 .stream()
42 .map(this::toDomain)
43 - .toList();
43 + .collect(Collectors.toSet()));
44 }
45
46 private Post toDomain(PostEntity entity) {
⎿ Found 4 new diagnostic issues in 1 file (ctrl+o to expand)
⏺ Done. Created Comments record and updated BlogRepository and JpaBlogRepository to use it.
✻ Baked for 31s
❯ write unit tests following our conventions for Comment, Comments, Author, Post, Posts
⏺ Write(domain/src/test/java/com/javablog/domain/blog/AuthorTest.java)
⎿ Wrote 26 lines to domain/src/test/java/com/javablog/domain/blog/AuthorTest.java
package com.javablog.domain.blog;
import com.javablog.domain.ConstraintViolationException;
import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.MethodSource;
import org.junit.jupiter.params.provider.NullAndEmptySource;
import java.util.stream.Stream;
import static org.assertj.core.api.Assertions.assertThatThrownBy;
… +16 lines (ctrl+o to expand)
⏺ Write(domain/src/test/java/com/javablog/domain/blog/CommentTest.java)
⎿ Wrote 32 lines to domain/src/test/java/com/javablog/domain/blog/CommentTest.java
package com.javablog.domain.blog;
import com.javablog.domain.ConstraintViolationException;
import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.Arguments;
import org.junit.jupiter.params.provider.MethodSource;
import java.util.stream.Stream;
import static com.javablog.domain.Fixture.*;
… +22 lines (ctrl+o to expand)
⏺ Write(domain/src/test/java/com/javablog/domain/blog/PostsTest.java)
⎿ Wrote 17 lines to domain/src/test/java/com/javablog/domain/blog/PostsTest.java
package com.javablog.domain.blog;
import com.javablog.domain.ConstraintViolationException;
import org.junit.jupiter.api.Test;
import static org.assertj.core.api.Assertions.assertThatThrownBy;
class PostsTest {
@Test
… +7 lines (ctrl+o to expand)
⏺ Write(domain/src/test/java/com/javablog/domain/blog/CommentsTest.java)
⎿ Wrote 17 lines to domain/src/test/java/com/javablog/domain/blog/CommentsTest.java
package com.javablog.domain.blog;
import com.javablog.domain.ConstraintViolationException;
import org.junit.jupiter.api.Test;
import static org.assertj.core.api.Assertions.assertThatThrownBy;
class CommentsTest {
@Test
… +7 lines (ctrl+o to expand)
⏺ Created tests for:
- AuthorTest - null, empty, whitespace invalid
- CommentTest - null for each of 5 fields
- PostsTest - null values invalid
- CommentsTest - null values invalid
PostTest already exists from earlier. Please run mvn test -pl domain to verify.
❯ In Guard.java - there should be no value value != null - reuse the againstNull. Introduce a simplified againstMaxLength(String value, String fieldName, int maxLength)
⏺ Read 1 file (ctrl+o to expand)
⏺ Update(domain/src/main/java/com/javablog/domain/Guard.java)
⎿ Added 9 lines, removed 1 line
26 }
27
28 public static void againstInvalidLength(String value, String fieldName, int min, int max) {
29 - if (value != null && (value.length() < min || value.length() > max)) {
29 + againstNull(value, fieldName);
30 + if (value.length() < min || value.length() > max) {
31 throw new ConstraintViolationException(fieldName + " must be between " + min + " and " + max + " characters");
32 }
33 }
34 +
35 + public static void againstMaxLength(String value, String fieldName, int maxLength) {
36 + againstNull(value, fieldName);
37 + if (value.length() > maxLength) {
38 + throw new ConstraintViolationException(fieldName + " must not exceed " + maxLength + " characters");
39 + }
40 + }
41 }
⎿ Found 1 new diagnostic issue in 1 file (ctrl+o to expand)
⏺ Now let me update Slug to use againstMaxLength instead.
⏺ Read 1 file (ctrl+o to expand)
⏺ Update(domain/src/main/java/com/javablog/domain/blog/Slug.java)
⎿ Added 1 line, removed 1 line
6
7 public Slug {
8 Guard.againstBlank(value, "Slug.value");
9 - Guard.againstInvalidLength(value, "Slug.value", 1, 255);
9 + Guard.againstMaxLength(value, "Slug.value", 255);
10 }
11 }
⏺ Searched for 1 pattern (ctrl+o to expand)
⏺ Done. Updated Guard to:
- Reuse againstNull in againstInvalidLength instead of inline null check
- Added againstMaxLength(String value, String fieldName, int maxLength)
- Updated Slug to use againstMaxLength
Note: againstInvalidLength is now unused. Let me know if you want it removed.
✻ Crunched for 39s
❯ remove it. also change the name to match the convention instead of againstMaxLength use againstInvalidLength
⎿ ⧉ Selected 1 lines from domain/src/main/java/com/javablog/domain/Guard.java in IntelliJ IDEA
⎿ Found 1 new diagnostic issue in 1 file (ctrl+o to expand)
⎿ Interrupted · What should Claude do instead?
❯ remove it. also change the name to match the convention instead of againstMaxLength use againstInvalidMaxLength
⏺ Update(domain/src/main/java/com/javablog/domain/Guard.java)
⎿ Added 1 line, removed 8 lines
25 }
26 }
27
28 - public static void againstInvalidLength(String value, String fieldName, int min, int max) {
28 + public static void againstInvalidMaxLength(String value, String fieldName, int maxLength) {
29 againstNull(value, fieldName);
30 - if (value.length() < min || value.length() > max) {
31 - throw new ConstraintViolationException(fieldName + " must be between " + min + " and " + max + " characters");
32 - }
33 - }
34 -
35 - public static void againstMaxLength(String value, String fieldName, int maxLength) {
36 - againstNull(value, fieldName);
30 if (value.length() > maxLength) {
31 throw new ConstraintViolationException(fieldName + " must not exceed " + maxLength + " characters");
32 }
⏺ Update(domain/src/main/java/com/javablog/domain/blog/Slug.java)
⎿ Added 1 line, removed 1 line
6
7 public Slug {
8 Guard.againstBlank(value, "Slug.value");
9 - Guard.againstMaxLength(value, "Slug.value", 255);
9 + Guard.againstInvalidMaxLength(value, "Slug.value", 255);
10 }
11 }
⎿ Found 1 new diagnostic issue in 1 file (ctrl+o to expand)
⏺ Done. Removed againstInvalidLength and renamed to againstInvalidMaxLength.
❯ ok, update the list of prompts we used in this session in home.html. I know it will be long, but we have a plan. Also update the domain claude.md to reflect the validation rules and how tests are
written.
⏺ Searched for 4 patterns, read 2 files (ctrl+o to expand)
⏺ Update(~/projects/2025/javablog.com/app/src/app/pages/home/home.html)
⎿ Added 19 lines
12 "we are going to work on a blog post and an additional part of the hexagonal architecture - our domain. Before we get started, lets define in the claude.md how our domain objects.
these records require validation annotations like @NotNull of @NotEmpty depending upon the business rules. For instance a BlogPost must have content so the BlogPost must have a
@NotEmpty String content element. where would this validation take place that the parameter provided is not null or empty?"
13 [Selected: Application service layer - Services use @Validated class annotation. Validation happens regardless of which adapter calls the service.]
14 "great - this is a new approach for me - typically I validate in the domain using a contraintsValidator.validate(this) in the domain record itself. I'm excited to validating at
the application/domain service level will play out. write the blog post and comment domain objects using annotations that align with the already provided database limitations. for instance,
title is not empty and maximum size 255 characters. Use the philosophy that everything is an object - Title has its own record that is used in the Post. all live in the blog package. Any
questions? Perhaps its best to just git it a try and we tweak it afterwards. Each domain object requires a UnitTest. We do not use Mockito in our domain. The unit test for a domain object
should always have a validateConstraints() test. If there are multiple parameters in a record constructor, then validateConstraints should be ParameterizedTest and the arguments should be
fed from a static validateConstraints function in the same test."
15 + "pretty good - under no circumstances should the primary validateConstraints test have a method source that isn't validateConstraints..."
16 + "null and empty values should not be added to the arguments tested in validateConstraints(). Better to use org.junit.jupiter.params.provider.NullAndEmptySource"
17 + "In the test code: com.javablog.domain define a class Fixture.java..."
18 + "ok, that worked. next topic - we want to no longer inherit from the spring-boot-starter-parent..."
19 + "great that worked fine. now lets introduce the maven-dependency-plugin:3.9.0..."
20 + "actually - make failOnWarning false and run a maven build to capture all of the warnings..."
21 + "remove warnings.txt and build-output.txt. update the tests to use the Fixture instead of constructing the records individually."
22 + "I've changed my mind after talking to a colleague today and do not want to try a variant of the same solution I've been using. lets keep the unit tests, but change the ways the
+validation is performed. Remove all annotations from the domain records."
23 + "I did not say to delete the validation tests - just the annotations. leave the tests. stop the procedure now."
24 + "alright - the domain is going to use an Uncle Bob classic 'Guard' class in the com.javablog.domain package. This guard class has a static function: Guard.againstNull(Object
+value, String fieldName); Instead of using an @NotNull annotation the compact constructor should be defined without parameters and refer the value, for instance in Title, to the
+Guard.againstNull(value, 'Title.value') implementation. If the object in againstNull is null - it should throw a ConstraintViolationException, a domain defined class that extends
+RuntimeException and prints a pretty message based upon the 'Title.value' helper and the context of the throwing function. write the Guard, apply it to Title, update the test to use assertj
+ to assert the exception is thrown with the appropriate exception instance and message."
25 + "its too early to execute the maven, the other tests need to be cleaned out first. change the other domain objects to use the Guard where appropriate. Add an additional
+Guard.againstEmpty. And Guard.againstInvalidLength. that should encompass all of the validations we were using. Update the domain classes to use these guards where we were using Annotations
+ before. Remove the static of() and other static constructors I didn't ask for."
26 + "remove the rest of the static of methods from the rest of the codebase."
27 + "haha - have a look at JpaBlogRepository"
28 + "Instead Of the BlogRepository.listPosts() returning a list of posts it should return a Posts object which takes a Set<Post> values in its constructor. The set may be empty,
+ but not null."
29 + "apply the same pattern to Comments. use a 'plural' domain object and its not allowed to have null values."
30 + "write unit tests following our conventions for Comment, Comments, Author, Post, Posts"
31 + "In Guard.java - there should be no value value != null - reuse the againstNull. Introduce a simplified againstMaxLength(String value, String fieldName, int maxLength)"
32 + "remove it. also change the name to match the convention instead of againstMaxLength use againstInvalidMaxLength"
33 + "ok, update the list of prompts we used in this session in home.html. I know it will be long, but we have a plan. Also update the domain claude.md to reflect the validation rules
+and how tests are written."
34
35
36
⏺ Write(domain/CLAUDE.md)
⎿ Wrote 155 lines to domain/CLAUDE.md
# Domain Layer Guidelines
Pure Java domain layer with no framework dependencies.
## Philosophy
- **Everything is an object** - Each concept gets its own record (Title, Slug, Content, Author, etc.)
- **No framework dependencies** - Domain remains pure Java
- **Validation in constructors** - Use Guard class for constraint enforcement
… +145 lines (ctrl+o to expand)
⏺ Now let me update the root CLAUDE.md to reflect the new Guard-based validation instead of annotations.
⏺ Update(~/projects/2025/javablog.com/CLAUDE.md)
⎿ Added 16 lines, removed 34 lines
135
136 ## Java Domain Objects
137
138 -Domain objects are Java records with Jakarta Bean Validation annotations.
138 +Domain objects are pure Java records with Guard-based validation. See `services/domain/CLAUDE.md` for detailed conventions.
139
140 -### Validation Annotations
140 +### Guard Pattern
141
142 -Use validation annotations based on business rules:
143 -- `@NotNull` - Field must not be null
144 -- `@NotEmpty` - String/collection must not be null or empty
145 -- `@NotBlank` - String must not be null and must contain at least one non-whitespace character
146 -- `@Size(min, max)` - String/collection size constraints
147 -- `@Pattern(regexp)` - String must match regex
142 +Validation uses the `Guard` class which throws `ConstraintViolationException` on failure:
143
144 -### Example Domain Record
145 -
144 ```java
145 -public record BlogPost(
146 - Long id,
147 - @NotBlank String title,
148 - @NotBlank String slug,
149 - @NotEmpty String content,
150 - @NotNull LocalDateTime publishedAt
151 -) {}
152 -```
145 +public record Title(String value) {
146
147 -### Validation Enforcement
148 -
149 -Validation is enforced at the **application service layer** using `@Validated`:
150 -
151 -```java
152 -@Service
153 -@Validated
154 -public class BlogPostService {
155 -
156 - public BlogPost createPost(@Valid BlogPost post) {
157 - // Validation runs before this method executes
158 - return repository.save(post);
147 + public Title {
148 + Guard.againstBlank(value, "Title.value");
149 }
150 }
151 ```
152
153 -This ensures:
154 -- Adapters (REST, CLI, events) remain thin
155 -- Validation happens regardless of which adapter calls the service
156 -- Invalid data never enters the domain logic
153 +### Available Guards
154
155 +- `Guard.againstNull(Object, String)` - must not be null
156 +- `Guard.againstEmpty(String, String)` - must not be null or empty
157 +- `Guard.againstBlank(String, String)` - must not be null, empty, or whitespace
158 +- `Guard.againstInvalidMaxLength(String, String, int)` - must not exceed max length
159 +
160 +### Everything is an Object
161 +
162 +Each domain concept gets its own record (Title, Slug, Content, Author, PostId, etc.). Collections use plural wrapper records (Posts, Comments).
163 +
164 ## Working Agreement (Java/Maven Services)
165
166 Claude writes code; Ben executes Maven commands. Do not run `mvn` commands directly. When verification is needed, ask Ben to run a specific command (e.g., "Please run `mvn compile` in the
services directory").
⏺ Done. Updated:
- app/src/app/pages/home/home.html - added all prompts from this session
- Created services/domain/CLAUDE.md - Guard pattern, testing conventions, Fixture usage
- Updated root CLAUDE.md - replaced annotation-based validation with Guard pattern summary
✻ Sautéed for 2m 17s
❯ one last prompt. in the home.html create a css class for the prompts - light grey. Create a horizontal divider in between the posts - like an hr but it could be a border bottom.
⏺ Searched for 3 patterns, read 3 files (ctrl+o to expand)
⏺ Update(~/projects/2025/javablog.com/app/src/app/pages/home/home.scss)
⎿ Added 15 lines
1 article {
2 + padding-bottom: 2rem;
3 + margin-bottom: 2rem;
4 + border-bottom: 1px solid #ddd;
5 +
6 + &:last-of-type {
7 + border-bottom: none;
8 + margin-bottom: 0;
9 + }
10 +
11 header {
12 margin-bottom: 2rem;
13
...
26 margin-bottom: 0.5rem;
27 }
28 }
29 +
30 + ul.prompts {
31 + background: #f5f5f5;
32 + padding: 1rem 1rem 1rem 2.5rem;
33 + border-radius: 4px;
34 + }
35 }
36 }
37
⏺ Now let me add the prompts class to all the prompt lists in home.html.
⏺ Update(~/projects/2025/javablog.com/app/src/app/pages/home/home.html)
⎿ Added 1 line, removed 1 line
19
20
21 Prompts Used
22 -
22 +
23 - "we are going to work on a blog post and the most important part of the application - our domain. Before we get started, lets define in the claude.md how our domain objects. these
records require validation annotations like @NotNull of @NotEmpty depending upon the business rules. For instance a BlogPost must have content so the BlogPost must have a
@NotEmpty String content element. where would this validation take place that the parameter provided is not null or empty?"
24 - [Selected: Application service layer - Services use @Validated class annotation. Validation happens regardless of which adapter calls the service.]
25 - "great - this is a new approach for me - typically I validate in the domain using a contraintsValidator.validate(this) in the domain record itself. I'm excited to validating at
the application/domain service level will play out. write the blog post and comment domain objects using annotations that align with the already provided database limitations. for instance,
title is not empty and maximum size 255 characters. Use the philosophy that everything is an object - Title has its own record that is used in the Post. all live in the blog package. Any
questions? Perhaps its best to just git it a try and we tweak it afterwards. Each domain object requires a UnitTest. We do not use Mockito in our domain. The unit test for a domain object
should always have a validateConstraints() test. If there are multiple parameters in a record constructor, then validateConstraints should be ParameterizedTest and the arguments should be
fed from a static validateConstraints function in the same test."
⏺ Update(~/projects/2025/javablog.com/app/src/app/pages/home/home.html)
⎿ Added 1 line, removed 1 line
98 target="_blank">Spring Boot 4.0 Migration Guide, ready for any human alive after May 2025 to read.
99
100
101 -
101 +
102 - "we are going to start living the hexagonal architecture as well as domain driven design. The domain should contain the objects that follow the principles of domain driven
design. In the package com.javablog.domain.blog create the following records: Post(), Comment(). Create a BlogRepository to listPosts() and listComments(Post). Implement the repository in
the adapter-persistence in the package com.javablog.adapter.persistence.blog. Note, use named queries that are anchored in the Entity object that lives in the adapter-persistence. Create a
PostEntity and CommentEntity in the same package as the BlogRepository. Each entity will have UUID as its identifier. Each entity will have a content member that contains text or varchar
with the maximum allowed. Do not use Clobs, Blobs - we will get to that later."
103 - [Multiple iterations of Claude adding flyway-core, configuration beans, and property changes—none worked]
104 - "no, you're hacking - admit you don't know what you are doing"
⏺ Update(~/projects/2025/javablog.com/app/src/app/pages/home/home.html)
⎿ Added 1 line, removed 1 line
141
142
143 Prompts Used
144 -
144 +
145 - "we are starting on post 4. this post will take our services application to the next level. Convert this project to a multi-module hexagonal architecture with five modules:
domain, application, adapter-rest, adapter-persistence, and bootstrap. Domain should have zero Spring dependencies. Application depends on domain with minimal Spring for Service
annotation. Adapter-rest depends on application and domain. Adapter-persistence depends on application and domain. Bootstrap depends on all four, contains the SpringBootApplication class,
application.properties, and spring-boot-maven-plugin. Add spring-boot-devtools as runtime optional in bootstrap for hot reload. Configure spring-boot-maven-plugin in bootstrap with
jvmArguments for JDWP debug on port 5005. The application must start successfully with mvn clean install && mvn -pl bootstrap spring-boot:run."
146 - "these changes should break the github action to deploy the services application. review the Dockerfile and api-deploy.yml to verify that the application will deploy given its
new architecture."
147 - "commit this and push this to test the github action again."
⏺ Update(~/projects/2025/javablog.com/app/src/app/pages/home/home.html)
⎿ Added 1 line, removed 1 line
199
{{ helloResponse() }}
200
201 Prompts Used
202 -
202 +
203 - "we are going to setup a rest services application to eventually permit comments and feedback for blog posts.
204 As this service will need a database and other services, let's assume it will run in a docker image running
205 inside a docker-compose constructed network. this project will require a sonar and nexus connection -
⏺ Update(~/projects/2025/javablog.com/app/src/app/pages/home/home.html)
⎿ Added 1 line, removed 1 line
285 this content is indexed. It's the long game with SEO - content and "safe" best practices. Cheers.
286
287
Prompts Used
288 -
288 +
289 - "the next few prompts will be public, including this one. I want to improve the SEO of my blog so that others can find my posts and be inspired to also experiment with 'vibing'
or 'LLM assisted coding'. The task today is to improve the SEO for the website https://javablog.com. The website has a single path that is currently visible - '/'. Create a sitemap.xml
that I can submit to the google search console. Also suggest an approach to SEO that: 1. works with translated content. 2. works in a single PR. 3. Can be extended later when there is more
content."
290 - "lets define a favicon.ico file that shows a capital 'J' in a darker purple with a background color white."
291 - "I have convert installed, you can run that command."
⏺ Update(~/projects/2025/javablog.com/app/src/app/pages/home/home.html)
⎿ Added 1 line, removed 1 line
330 - GitHub Actions for CI/CD
331
332 My Prompts
333 -
333 +
334 - "you now should have access to javablog.com... I want to use it to make posts. I think given your talents - we will not use a blogging tool, instead we will just create content.
create a claude.md for you to follow"
335 - "You took it too far. I want an angular application app to live in an app directory. when the github action triggers, it should build the app and deploy it to azure."
336 - "I want it built from day one to be SEO and AI friendly."
⏺ Done. Added:
- .prompts class with light grey background (#f5f5f5)
- Horizontal divider between posts using border-bottom on articles (removed on last article)
- Applied class="prompts" to all 6 prompt lists
✻ Churned for 1m 1s