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# StringBuilderNew

Create a new StringBuilder instance or wrap an existing Java StringBuilder.

## Method Signature

```
StringBuilderNew(value=[any], capacity=[integer])
```

### Arguments

| Argument   | Type      | Required | Description                                                                                    | Default |
| ---------- | --------- | -------- | ---------------------------------------------------------------------------------------------- | ------- |
| `value`    | `any`     | `false`  | Optional initial value (String) or existing Java StringBuilder to wrap. Empty if not provided. |         |
| `capacity` | `integer` | `false`  | Optional initial capacity for newly created BoxStringBuilder instances.                        | `0`     |

## Examples

### Create a StringBuilder with stringBuilderNew()

Creates a new StringBuilder instance.

```java
result = stringBuilderNew();
writeOutput( result.toString() );
```

Result: (empty string)

### Create a seeded StringBuilder

```java
result = stringBuilderNew( 'hello' );
writeOutput( result.toString() );
```

Result: hello

### Create an empty StringBuilder with explicit capacity

```java
result = stringBuilderNew( capacity = 64 );
writeOutput( result.getBuffer().capacity() );
```

Result: at least 64

### Create a seeded StringBuilder with explicit capacity

```java
result = stringBuilderNew( 'hello', 64 );
writeOutput( result.toString() );
```

Result: hello

## Related

* [StringBuilderAppend](/boxlang-language/reference/built-in-functions/stringbuilder/stringbuilderappend.md)
* [StringBuilderClear](/boxlang-language/reference/built-in-functions/stringbuilder/stringbuilderclear.md)
* [StringBuilderContains](/boxlang-language/reference/built-in-functions/stringbuilder/stringbuildercontains.md)
* [StringBuilderDelete](/boxlang-language/reference/built-in-functions/stringbuilder/stringbuilderdelete.md)
* [StringBuilderEndsWith](/boxlang-language/reference/built-in-functions/stringbuilder/stringbuilderendswith.md)
* [StringBuilderFind](/boxlang-language/reference/built-in-functions/stringbuilder/stringbuilderfind.md)
* [StringBuilderInsert](/boxlang-language/reference/built-in-functions/stringbuilder/stringbuilderinsert.md)
* [StringBuilderLeft](/boxlang-language/reference/built-in-functions/stringbuilder/stringbuilderleft.md)
* [StringBuilderMid](/boxlang-language/reference/built-in-functions/stringbuilder/stringbuildermid.md)
* [StringBuilderPrepend](/boxlang-language/reference/built-in-functions/stringbuilder/stringbuilderprepend.md)
* [StringBuilderReplace](/boxlang-language/reference/built-in-functions/stringbuilder/stringbuilderreplace.md)
* [StringBuilderReverse](/boxlang-language/reference/built-in-functions/stringbuilder/stringbuilderreverse.md)
* [StringBuilderRight](/boxlang-language/reference/built-in-functions/stringbuilder/stringbuilderright.md)
* [StringBuilderStartsWith](/boxlang-language/reference/built-in-functions/stringbuilder/stringbuilderstartswith.md)
* [StringBuilderTrim](/boxlang-language/reference/built-in-functions/stringbuilder/stringbuildertrim.md)


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