# Business Logic — ObjectsFilter.evaluate() [14 LOC]

| Field | Value |
|-------|-------|
| Fully Qualified Name | `eo.web.webview.KKW01021SF.ObjectsFilter` |
| Layer | Utility (Inner class within a screen logic class, `eo.web.webview` package — webview utility component) |
| Module | `KKW01021SF` (Package: `eo.web.webview.KKW01021SF`) |

## 1. Role

### ObjectsFilter.evaluate()

`ObjectsFilter.evaluate()` is a reusable predicate implementation that performs membership checking on a `HashMap` entry's value against a predefined set of acceptable values. It answers the business question "does this particular field's current value belong to the allowed set?" — a common filter decision used throughout the screen logic when processing lists of items, such as validating whether a record's category, type, or status code is one that should be included in the current operation.

The method implements the **Predicate (Filter) design pattern** as part of the `Items` collection utility framework. It is not called directly by business logic; instead, it is invoked indirectly through the `Items.exist()`, `Items.find()`, and `Items.select()` static helper methods, which accept a `Predicater<I>` instance to filter collections. This delegation pattern enables generic, composable filtering across diverse data structures without embedding filter logic inline.

The method is a **shared utility** nested inside `KKW01021SFLogic.java`, meaning it is a screen-specific predicate tailored for the `KKW01021SF` screen's filtering requirements. It can be instantiated with any key (map field name) and any set of acceptable values, making it a highly parameterized and reusable filter.

## 2. Processing Pattern (Detailed Business Logic)

```mermaid
flowchart TD
    START(["evaluate(item)"])
    ITEM_GET["itemValue = item.get(key)"]
    LOOP_START{"for each value in values"}
    VALUE_MATCH{"value.equals(itemValue)"}
    RETURN_TRUE["return true — match found"]
    RETURN_FALSE["return false — no match"]
    END_NODE(["End — next iteration or return false"])

    START --> ITEM_GET
    ITEM_GET --> LOOP_START
    LOOP_START --> VALUE_MATCH
    VALUE_MATCH -- "match found" --> RETURN_TRUE
    VALUE_MATCH -- "no match" --> END_NODE
    END_NODE --> LOOP_START
```

**Processing summary:**
The method extracts a single field value from the input map using the pre-configured key, then iterates through a predefined array of acceptable values. If any value equals the extracted item value (using `equals()`), it returns `true` immediately (short-circuit). If the loop exhausts all values without a match, it returns `false`.

**Constants resolved:** No constants are referenced within the `evaluate()` method body. The `key` and `values` fields are injected at construction time via the `ObjectsFilter(String key, Object[] values)` constructor, and their resolved values are determined by the caller at instantiation (not at evaluation time).

## 3. Parameter Analysis

| No | Parameter Name | Type | Business Description |
|----|---------------|------|---------------------|
| 1 | `item` | `HashMap<String, Object>` | A single map-represented data record (typically a row or entity snapshot) whose field value is being tested against an allowed set. The key determines which field within the map is evaluated, and the value at that key is compared against the pre-configured `values` array. |

**Instance fields read:**

| Field | Type | Business Description |
|-------|------|---------------------|
| `key` | `String` | The map key (field name) whose value is being checked. Set at construction time to identify the target field (e.g., a status code or category identifier). |
| `values` | `Object[]` | The array of acceptable values for the given `key`. Represents the "whitelist" of values that should cause the predicate to return `true`. |

## 4. CRUD Operations / Called Services

This method performs **no CRUD operations** and makes **no service calls**. It is a pure in-memory predicate that only reads data from its input `HashMap` and its own fields.

| CRUD | SC / CBS | SC Code | Entity / DB | Operation Description |
|------|----------|---------|-------------|----------------------|
| *(none)* | — | — | — | This method performs only in-memory equality checks. No database, SC, or CBS interactions occur. |

## 5. Dependency Trace

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

Callers found: `Items.exist()`, `Items.find()`, `Items.select()`.

`ObjectsFilter.evaluate()` is an inner class implementing `Predicater<HashMap<String, Object>>`. It is never called directly from screen or batch entry points. Instead, it is passed as a predicate to the static `Items` helper methods, which iterate over collections and delegate the evaluation to this method.

| # | Caller (Screen/Batch) | Call Chain (Full Path to this Method) | Terminal (SC / CRUD / Entity) |
|---|----------------------|--------------------------------------|-------------------------------|
| 1 | Items.exist() | `Items.exist(in, pred)` → `pred.evaluate(item)` | *(none — pure in-memory predicate)* |
| 2 | Items.find() | `Items.find(in, pred)` → `pred.evaluate(item)` | *(none — pure in-memory predicate)* |
| 3 | Items.select() | `Items.select(in, pred)` → `pred.evaluate(item)` | *(none — pure in-memory predicate)* |

**Call chain details:**
- `Items.exist(ArrayList<I> in, Predicater<I> predicater)` — Iterates a collection and returns `true` if any element satisfies the predicate. Used for existence checks (e.g., "does any item in this list match the filter criteria?").
- `Items.find(ArrayList<I> in, Predicater<I> predicater)` — Returns the first element in a collection that satisfies the predicate. Used for lookups (e.g., "find the first matching record").
- `Items.select(ArrayList<I> in, Predicater<I> predicater)` — Returns all elements in a collection that satisfy the predicate. Used for filtered queries (e.g., "return all records matching these criteria").

All three callers are static utility methods defined in `Items` class (same file as `ObjectsFilter`), providing a generic, composable filtering API used throughout the `KKW01021SF` screen logic.

## 6. Per-Branch Detail Blocks

**Block 1** — METHOD_ENTRY `(start of evaluate)` (L1658)

The method is entered with a `HashMap<String, Object>` item. This block performs the initial field extraction from the map.

| # | Type | Code |
|---|------|------|
| 1 | SET | `itemValue = item.get(key);` // Extract the value for the configured key from the input map |

**Block 2** — FOR_LOOP `(for each value in values)` (L1661)

Iterates through the pre-configured array of acceptable values to find a match.

| # | Type | Code |
|---|------|------|
| 1 | EXEC | `for (Object value : values)` // Iterate over each acceptable value in the whitelist |

**Block 2.1** — IF `(value.equals(itemValue))` (L1663)

Nested inside the loop. Checks whether the current acceptable value equals the extracted map value. This is a value-equality comparison, not a reference comparison.

| # | Type | Code |
|---|------|------|
| 1 | EXEC | `value.equals(itemValue)` // Compare acceptable value against the map field value |

**Block 2.1.1** — RETURN `(match found → true)` (L1665)

If the current value matches, the predicate is satisfied. Return `true` immediately (short-circuit — remaining values are not checked).

| # | Type | Code |
|---|------|------|
| 1 | RETURN | `return true;` // Item's value is in the allowed set — filter passes |

**Block 2.2** — LOOP_CONTINUE `(no match → next value)` (L1666)

If the current value does not match, the loop continues to the next acceptable value. No explicit action needed — the loop naturally proceeds to the next element.

**Block 3** — RETURN_FALSE `(end of loop without match)` (L1668)

If the loop exhausts all values without finding a match, the item's value is not in the allowed set. Return `false`.

| # | Type | Code |
|---|------|------|
| 1 | RETURN | `return false;` // Item's value is not in the allowed set — filter fails |

## 7. Glossary

| Term | Type | Business Meaning |
|------|------|------------------|
| `ObjectsFilter` | Class | A predicate utility class that checks whether a map entry's value belongs to a predefined set of acceptable values. Used for filtering collections within the screen logic. |
| `Predicater<I>` | Interface | A generic functional interface defining a single `evaluate(I input)` method that returns `boolean`. Implements the Predicate design pattern for collection filtering. |
| `key` | Field | The map key (String) identifying which field within the input `HashMap` should be evaluated. Set at object construction time. |
| `values` | Field | An array of `Object` representing the set of acceptable values for the given key. Set at object construction time. |
| `item` | Parameter | A `HashMap<String, Object>` representing a single data record (e.g., a row from a query result or a business entity snapshot). |
| `itemValue` | Local var | The value extracted from the `item` map at the configured `key`. This is the value being tested for membership in the `values` array. |
| `Items` | Utility class | A static utility class containing collection helper methods (`exist`, `find`, `select`, `map`, `each`) that operate on `ArrayList` collections using `Predicater`, `Closure`, and `Transformer` functional interfaces. |
| `exist` | Method | `Items.exist(ArrayList, Predicater)` — Checks if any element in a collection satisfies a predicate. Returns `boolean`. |
| `find` | Method | `Items.find(ArrayList, Predicater)` — Finds and returns the first element in a collection that satisfies a predicate. |
| `select` | Method | `Items.select(ArrayList, Predicater)` — Returns all elements in a collection that satisfy a predicate as a new list. |