---

# (DD15) Business Logic — Example.lines() [7 LOC]

| Field | Value |
|-------|-------|
| Fully Qualified Name | `io.github.biezhi.java11.string.Example` |
| Layer | Utility |
| Module | `string` (Package: `io.github.biezhi.java11.string`) |

## 1. Role

### Example.lines()

This method is a small demonstration utility for the JDK 11 `String.lines()` API. It presents a fixed multi-line text sample, splits that text into individual logical lines, and prints the resulting list to standard output. In business terms, it acts as a reference implementation for how a text payload containing embedded line separators can be normalized into line-level records. The method does not branch by service type or business category; instead, it provides a single happy-path example of line extraction and list materialization. Its main role in the larger system is educational: it supports the `string` package examples and is invoked from the class entry point to show the runtime effect of the API. The processing pattern follows simple routing-by-example: initialize a header, create a sample string, convert the string into a stream of lines, collect the stream into a list, and display the result.

## 2. Processing Pattern (Detailed Business Logic)

```mermaid
flowchart TD
    START(["lines()"])
    A["Call writeHeader(\"String.lines()\")"]
    B["Set str to multiline literal"]
    C["Call str.lines()"]
    D["Collect stream to List"]
    E["Print resulting List"]
    END_NODE(["Return"])
    START --> A
    A --> B
    B --> C
    C --> D
    D --> E
    E --> END_NODE
```

**CRITICAL — Constant Resolution:**
No application constants, constant classes, or code-controlled branch constants are referenced in this method. The method uses only an inline string literal.

## 3. Parameter Analysis

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

External state read by the method:
- `writeHeader(...)` from the enclosing `Example` utility context.
- `System.out` for console output.
- `Collectors.toList()` for stream materialization.
- The `String.lines()` runtime API behavior, which interprets embedded line separators in the sample text.

## 4. CRUD Operations / Called Services

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

| CRUD | SC / CBS | SC Code | Entity / DB | Operation Description |
|------|----------|---------|-------------|----------------------|
| - | `Example.writeHeader` | Example | - | Calls `writeHeader` in `Example` |

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 | `Example.writeHeader` | Example | - | Writes a section header for the console demonstration before the line-splitting example runs. |
| R | `String.lines` | JDK 11 API | - | Reads the embedded text and exposes each logical line as a stream element. |
| R | `Collectors.toList` | JDK Stream API | - | Aggregates the stream of lines into a list for display. |
| R | `System.out.println` | JDK Standard Library | - | Outputs the collected line list to the console. |

## 5. Dependency Trace

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

No screen/batch entry points found within 8 hops. Direct callers found: 1 methods.
Terminal operations from this method: `writeHeader` [-]

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 | Utility:Example.main | `Example.main(String[] args)` -> `Example.lines()` | `writeHeader [R] -` |

## 6. Per-Branch Detail Blocks

The method contains a single straight-line execution path with no branching, looping, or exception handling.

**Block 1** — [SEQUENCE] (L96–L102)

> Demonstrates the `String.lines()` API by preparing a sample text, splitting it into lines, and printing the collected result.

| # | Type | Code |
|---|------|------|
| 1 | CALL | `writeHeader("String.lines()");` |
| 2 | SET | `String str = "Hello 
 World, I,m
biezhi.";` |
| 3 | EXEC | `str.lines()` |
| 4 | CALL | `Collectors.toList()` |
| 5 | EXEC | `System.out.println(...)` |
| 6 | RETURN | `return;` |

## 7. Glossary

| Term | Type | Business Meaning |
|------|------|------------------|
| `lines` | Method name | JDK 11 string utility example that converts a multi-line text value into separate logical line items. |
| `writeHeader` | Method | Shared console helper that prints a section title for the example output. |
| `String.lines()` | JDK API | Returns a stream of lines extracted from a string using line-separator boundaries. |
| `Collectors.toList()` | JDK API | Collects stream elements into a list for presentation. |
| `System.out` | Runtime output | Standard console output channel used to display example results. |
| `String` | Java type | Immutable text value used as the sample payload in this demonstration. |
| `multiline literal` | Technical term | A string containing embedded newline characters that produce multiple logical lines. |
| `Utility` | Layer | Supporting code that demonstrates or assists application behavior rather than implementing business orchestration. |
| `JDK 11` | Platform term | Java runtime version that introduced the `String.lines()` convenience API. |