# (DD37) Business Logic — ClinicServiceTests.shouldFindOwnersByLastName() [8 LOC]

| Field | Value |
|-------|-------|
| Fully Qualified Name | `org.springframework.samples.petclinic.service.ClinicServiceTests` |
| Layer | Service Test / Integration Test |
| Module | `service` (Package: `org.springframework.samples.petclinic.service`) |

## 1. Role

### ClinicServiceTests.shouldFindOwnersByLastName()

This test method verifies the owner search behavior exposed through the Spring Data repository layer for the PetClinic domain. It validates that a last-name prefix lookup returns the expected number of owner records when the prefix matches existing data, and that the same lookup returns no records when the prefix does not match. In business terms, the method confirms that the owner search capability can support an end-user screen or service flow that looks up customers by surname fragment and needs deterministic pagination-independent results.

The method acts as a repository contract test rather than a business workflow implementation. It uses a simple read-only verification pattern: call the repository, inspect the returned page, and assert the result count. The test covers two branches of the same search behavior: a successful prefix match for `Davis`, and a negative case for the misspelled prefix `Daviss`. As a result, it provides confidence that the data access layer correctly filters owners by surname prefix and does not over-return unrelated rows.

## 2. Processing Pattern (Detailed Business Logic)

```mermaid
flowchart TD
    START(["shouldFindOwnersByLastName()"])
    QUERY1(["Call ownerRepository.findByLastNameStartingWith('Davis', Pageable.unpaged())"])
    ASSERT1(["Assert result size is 2"])
    QUERY2(["Call ownerRepository.findByLastNameStartingWith('Daviss', Pageable.unpaged())"])
    ASSERT2(["Assert result is empty"])
    END_NODE(["End"])

    START --> QUERY1
    QUERY1 --> ASSERT1
    ASSERT1 --> QUERY2
    QUERY2 --> ASSERT2
    ASSERT2 --> END_NODE
```

## 3. Parameter Analysis

| No | Parameter Name | Type | Business Description |
|----|---------------|------|---------------------|
| - | (none) | - | - |

External state read by the method:
- `this.owners` — injected `OwnerRepository` used to query owner data.
- `pageable` — class-level `Pageable.unpaged()` instance used to request the full result set without pagination limits.

## 4. CRUD Operations / Called Services

### Pre-computed evidence from code analysis graph:

| CRUD | SC / CBS | SC Code | Entity / DB | Operation Description |
|------|----------|---------|-------------|----------------------|
| R | `OwnerRepository.findByLastNameStartingWith` | OwnerRepository | Owner | Calls `findByLastNameStartingWith` in `OwnerRepository` |

Analyze all method calls within this method and classify each as a CRUD operation.
Use the pre-computed evidence above. If SC Code or Entity/DB is missing, try to infer from:
- The **SC Code** (Service Component code, e.g., `EKK0361A010SC`, `EKK1081D010CBS`) — look at the class name of the called method or its containing class.
- The **Entity/DB tables** — search for table name constants (often `KK_T_*` pattern), SQL references, or entity names in the called method's source code.

| CRUD | SC / CBS | SC Code | Entity / DB | Operation Description |
|------|----------|---------|-------------|----------------------|
| R | `findByLastNameStartingWith` | `OwnerRepository` | `Owner` | Reads owner records whose last name begins with the supplied prefix and returns them as a page. |
| R | `assertThat(...).hasSize(2)` | - | - | Verifies the returned page contains exactly two matching owners for the expected surname prefix. |
| R | `assertThat(...).isEmpty()` | - | - | Verifies the negative lookup returns no owner records for the misspelled surname prefix. |

## 5. Dependency Trace

Trace who calls this method and what this method ultimately calls.
Use the pre-computed evidence and caller search results from Step 2 above.

| # | Caller (Screen/Batch) | Call Chain (Full Path to this Method) | Terminal (SC / CRUD / Entity) |
|---|----------------------|--------------------------------------|-------------------------------|
| 1 | No direct Java caller found | JUnit 5 test runner -> `ClinicServiceTests.shouldFindOwnersByLastName()` | `findByLastNameStartingWith [R] Owner` |

**Instructions:**
- Use `search_files` with pattern `**/*.java` and content_pattern `shouldFindOwnersByLastName` to find all callers.
- For each caller, identify if it's a Screen (class name contains `KKSV*`, `Screen*`), Batch, Controller, or CBS.
- Build the full call chain from the entry point to this method.
- Each row = one unique entry point. Show ALL found callers (up to 15 rows).
- The Terminal column lists ALL CRUD endpoints reached FROM this method.
- Format terminal as: `methodName [C/R/U/D] EntityOrTableName`
- If a caller class name matches `KKSV\d{4}`, format as `Screen:KKSVxxxx`.

## 6. Per-Branch Detail Blocks

Analyze the method's control flow block by block. Analyze ALL nesting levels — no depth limit.

> Each branch of the control flow is displayed as a hierarchical block structure.

**Format to follow:**

**Block 1** — [SEQUENCE] `(no condition)` (L87)

> Executes the owner lookup for the matching surname prefix and validates the primary positive case.

| # | Type | Code |
|---|------|------|
| 1 | SET | `Page<Owner> owners = this.owners.findByLastNameStartingWith("Davis", pageable);` |
| 2 | CALL | `this.owners.findByLastNameStartingWith("Davis", pageable);` |
| 3 | CALL | `assertThat(owners).hasSize(2);` |

**Block 2** — [SEQUENCE] `(no condition)` (L90)

> Executes the second lookup to confirm the repository returns no records for a non-matching prefix.

| # | Type | Code |
|---|------|------|
| 1 | SET | `owners = this.owners.findByLastNameStartingWith("Daviss", pageable);` |
| 2 | CALL | `this.owners.findByLastNameStartingWith("Daviss", pageable);` |
| 3 | CALL | `assertThat(owners).isEmpty();` |

## 7. Glossary

Define ALL domain-specific terms, Japanese field names, and technical abbreviations used in this method. This section makes the document accessible to Business Analysts (BA) who may not be familiar with the codebase's naming conventions.

**Include at minimum:**
- Every Japanese-named field (e.g., `svc_kei_ucwk_no`, `odr_naiyo_cd`) with its business meaning
- Every acronym (e.g., SOD, JOKEN, INFO, FTTH) with its expansion
- Every service type referenced (e.g., FTTH, Mail, ENUM) with its domain description

**Format:**

| Term | Type | Business Meaning |
|------|------|------------------|
| `Owner` | Entity | PetClinic customer record representing an owner of one or more pets. |
| `OwnerRepository` | Repository | Spring Data repository used to read and persist owner data. |
| `Pageable` | Technical term | Paging abstraction that controls page size and navigation; `Pageable.unpaged()` requests the full result set. |
| `Page<Owner>` | Technical term | Paginated container for owner search results. |
| `last name` | Business term | Owner surname used as the search key in the lookup. |
| `prefix search` | Business term | Search mode that matches owners whose last name starts with the supplied text. |
| `Davis` | Test data | Expected matching surname prefix used in the positive assertion. |
| `Daviss` | Test data | Non-matching surname prefix used in the negative assertion. |