# Business Logic — Example.demonstrateStringStripTrailing() [6 LOC]

| Field | Value |
|-------|-------|
| Fully Qualified Name | `io.github.biezhi.java11.string.Example` |
| Layer | Utility (Example class with demonstration/example methods) |
| Module | `string` (Package: `io.github.biezhi.java11.string`) |

## 1. Role

### Example.demonstrateStringStripTrailing()

This method serves as a **Java 11 API feature demonstration** for the `String.stripTrailing()` method, which was introduced in JDK 11. It illustrates how to remove trailing whitespace characters (spaces, tabs, and Unicode whitespace) from the end of a string without affecting leading whitespace. The method operates as a **shared utility/demo entry point** — it is the kind of example method commonly found in learning or showcase codebases (such as the "123 Java Tips" project by biezhi) to help developers understand new language features. It follows a **delegation pattern**: it prepares a sample string containing both leading and trailing spaces, delegates the display of metadata to `writeHeader()`, and delegates the actual string transformation to `String.stripTrailing()`, printing the result. The method does not perform any conditional branching, CRUD operations, or complex business logic — its sole purpose is educational demonstration of a JDK 11 standard library addition.

## 2. Processing Pattern (Detailed Business Logic)

```mermaid
flowchart TD
    START(["demonstrateStringStripTrailing"])
    STEP1(["Declare originalString = literal string with leading and trailing spaces"])
    STEP2(["Call writeHeader to print method info and original string value"])
    STEP3(["Call System.out.println with stripTrailing result"])
    END(["Return void"])

    START --> STEP1
    STEP1 --> STEP2
    STEP2 --> STEP3
    STEP3 --> END
```

This method executes sequentially with **no conditional branches**. Each step is:

1. **Declare** a hardcoded string literal with intentional leading and trailing whitespace for demonstration purposes.
2. **Call** `writeHeader()` to print a formatted header line identifying the method being demonstrated, including the original string value in the output.
3. **Call** `System.out.println()` with the result of `stripTrailing()` applied to the original string, showing the output with trailing whitespace removed (leading whitespace is preserved).

## 3. Parameter Analysis

| No | Parameter Name | Type | Business Description |
|----|---------------|------|---------------------|
| - | (none) | - | This method takes no parameters. It operates entirely on hardcoded local data. |

**Local variables and external state:**

| # | Name | Type | Business Description |
|---|------|------|---------------------|
| 1 | `originalString` | `java.lang.String` | A hardcoded literal `"  biezhi.me  23333  "` containing both leading and trailing whitespace. Used as the demonstration subject for `stripTrailing()`. |
| 2 | `writeHeader(String)` | method reference | A static method in the same `Example` class used to print a formatted header section before each demonstration output. |

## 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` to print a formatted header |
| - | `System.out.println` | `System` | - | Standard output — prints the demonstration result to console |

**Classification:**

| CRUD | SC / CBS | SC Code | Entity / DB | Operation Description |
|------|----------|---------|-------------|----------------------|
| - | `Example.writeHeader` | Example | - | Prints a formatted header line identifying the demonstration method and showing the original string value. No data access. |
| - | `System.out.println` | `System` | - | Writes the demonstration result (stripped string) to standard output. No data access. |

This method performs **no database or entity operations**. It is a pure console demonstration.

## 5. Dependency Trace

| # | Caller (Screen/Batch) | Call Chain (Full Path to this Method) | Terminal (SC / CRUD / Entity) |
|---|----------------------|--------------------------------------|-------------------------------|
| 1 | N/A | *(no active callers — method is called only via commented-out reference on line 109 of the same file)* | - |

**Notes:**
- This method has **no active callers** in the codebase. It is referenced only in a commented-out line (line 109 of `Example.java`) suggesting it may have been called from another demonstration method in the same class.
- The method itself is a **standalone demo entry point** and is not invoked by any screen, batch, or service component.
- It does not call any SC/CBS, CRUD, or entity-level operations.

## 6. Per-Branch Detail Blocks

This method contains **no control flow blocks** (no if/else, switch, loops, or try/catch). It executes as a single straight-line sequence.

**Block 1** — [SEQUENTIAL EXECUTION] (L69–L74)

| # | Type | Code |
|---|------|------|
| 1 | SET | `String originalString = "  biezhi.me  23333  ";` // Hardcoded demonstration string with leading and trailing whitespace |
| 2 | CALL | `writeHeader("String.stripTrailing() on '" + originalString + "'");` // Prints formatted header with method name and original string value |
| 3 | EXEC | `System.out.println("'" + originalString.stripTrailing() + "'");` // Applies `stripTrailing()` to remove trailing whitespace, prints result |

**Expected output:**
- Header line: `String.stripTrailing() on '  biezhi.me  23333  '`
- Output line: `'  biezhi.me  23333'` (note: leading spaces preserved, trailing spaces removed)

## 7. Glossary

| Term | Type | Business Meaning |
|------|------|------------------|
| `stripTrailing()` | JDK 11 API | A method on `java.lang.String` introduced in Java 11 that returns a new string with trailing whitespace characters removed. Leading whitespace is preserved. Equivalent to `strip()` but only removes from the end. |
| `writeHeader()` | Utility method | A static helper method in the `Example` class that prints a formatted section header (typically a decorative border and title) before each demonstration. |
| `originalString` | Local variable | A hardcoded string literal used as the demonstration subject. Contains the text "biezhi.me  23333" with leading and trailing spaces to show the before/after effect of `stripTrailing()`. |
| JDK 11 | Platform version | Java Development Kit version 11, where `String.stripTrailing()` was added as part of the String API improvements in Java 11 (JEP 322). |
| biezhi.me | Domain | The website of the project author (Wei Wang / biezhi), who maintains the "123 Java Tips" GitHub project containing this demonstration code. |

---

*Generated for enterprise documentation standard. Method is a JDK 11 feature demonstration with no business logic, no data access, and no callers.*