Package jjparse.input

Class Input<T>

java.lang.Object

jjparse.input.Input<T>

Type Parameters:

T - The covariant element type for this Input. In most cases this type equals Character.

Direct Known Subclasses:

CharacterInput, StreamInput

public abstract class Input<T>
extends Object

An abstract representation of an Input for parsing. In most cases, this will be a CharacterInput, which is an Input of Characters and can be considered a sequence of characters (just like a String).

Note: This class is intended to be immutable and hence covariant in its type parameter.

Author:

Björn Lötters

See Also:

• Parsing.Parser
• CharacterInput
• StreamInput

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
class	Input.Position	Represents an offset within this Input.

Field Summary

Fields

Modifier and Type	Field	Description
final String	name	A human-readable name for this Input which can be used for error reporting purposes.

Constructor Summary

Constructors

Constructor	Description
Input(String name)	Constructs a new Input on basis of the provided name.

Method Summary

Modifier and Type	Method	Description
static <T> Input<T>	empty()	Constructs an empty Input of an arbitrary element type where "<empty>" is used as the name.
abstract T	head()	Returns the first element of this Input.
abstract boolean	isEmpty()	Checks whether this Input is empty.
final boolean	nonEmpty()	Checks whether this Input is not empty.
static Input<Character>	of(String name, byte[] bytes, Charset charset)	Constructs a new Input of Characters on basis of the provided Byte array and Charset.
static Input<Character>	of(String name, InputStream stream, Charset charset)	Constructs a new Input of Characters on basis of the provided InputStream and Charset.
static Input<Character>	of(String name, CharSequence sequence)	Constructs a new Input of Characters on basis of the provided CharSequence.
static <T> Input<T>	of(String name, Iterable<T> iterable)	Constructs a new Input on basis of the provided Iterable.
static <T> Input<T>	of(String name, Iterator<T> iterator)	Constructs a new Input on basis of the provided Iterator.
static <T> Input<T>	of(String name, Stream<T> stream)	Constructs a new Input on basis of the provided Stream.
static Input<Character>	of(Path path, Charset charset)	Constructs a new Input of Characters on basis of the provided file Path and Charset.
abstract Input<T>.Position	position()	A Input<T>.Position that points to the first element in this Input.
abstract Input<T>	tail()	Returns the rest of this Input, excluding its first element.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

name

public final String name

A human-readable name for this Input which can be used for error reporting purposes.

Constructor Details

Input

public Input(String name)

Constructs a new Input on basis of the provided name.

Parameters:

name - A human-readable name for this Input, which is primarily used for error reporting purposes.

Method Details

isEmpty

public abstract boolean isEmpty()

Checks whether this Input is empty.

Returns:

true if this Input is empty.

See Also:

• nonEmpty()

nonEmpty

public final boolean nonEmpty()

Checks whether this Input is not empty.

Returns:

true if this Input is not empty.

See Also:

• isEmpty()

head

public abstract T head()
                throws NoSuchElementException

Returns the first element of this Input. If this Input is empty, an exception is thrown.

Returns:

The first element of this Input.

Throws:

NoSuchElementException - If this Input is empty.

See Also:

• isEmpty()
• tail()

tail

public abstract Input<T> tail()

Returns the rest of this Input, excluding its first element. If this Input is empty, an empty Input is returned.

Returns:

The rest of this Input or an empty Input, if this Input is empty.

See Also:

• isEmpty()
• head()

position

public abstract Input<T>.Position position()

A Input<T>.Position that points to the first element in this Input.

Returns:

The Input<T>.Position of the first element in this Input.

empty

public static <T> Input<T> empty()

Constructs an empty Input of an arbitrary element type where "<empty>" is used as the name.

Type Parameters:

T - The element type.

Returns:

An empty Input of an arbitrary element type.

of

public static <T> Input<T> of(String name,
 Iterator<T> iterator)

Constructs a new Input on basis of the provided Iterator.

Type Parameters:

T - The element type of the Input and the Iterator.

Parameters:

name - A human-readable name for the Input.

iterator - The underlying Iterator that provides the elements for the Input.

Returns:

An Input over the provided Iterator.

of

public static <T> Input<T> of(String name,
 Iterable<T> iterable)

Constructs a new Input on basis of the provided Iterable.

Type Parameters:

T - The element type of the Input and the Iterable.

Parameters:

name - A human-readable name for the Input.

iterable - The underlying Iterable that provides the elements for the Input.

Returns:

An Input over the provided Iterable.

of

public static <T> Input<T> of(String name,
 Stream<T> stream)

Constructs a new Input on basis of the provided Stream.

Type Parameters:

T - The element type of the Input and the Stream.

Parameters:

name - A human-readable name for the Input.

stream - The underlying Stream that provides the elements for the Input.

Returns:

An Input over the provided Stream.

of

public static Input<Character> of(String name,
 InputStream stream,
 Charset charset)
                           throws IOException

Constructs a new Input of Characters on basis of the provided InputStream and Charset. Take note that the provided InputStream is completely read before the Input is created. For a lazy kind of input, consider one of the other variants of this method.

Parameters:

name - A human-readable name for the Input.

stream - The underlying source for this Input.

charset - The Charset that shall be used to decode the InputStream.

Returns:

An Input of Characters that is based on the underlying InputStream.

Throws:

IOException - If reading from the InputStream fails.

of

public static Input<Character> of(Path path,
 Charset charset)
                           throws IOException

Constructs a new Input of Characters on basis of the provided file Path and Charset.

Parameters:

path - The Path to the file that should be read as the source of this input. At the same time, this path is used as the name for the Input.

charset - The Charset that shall be used to decode the file denoted by the provided Path.

Returns:

An Input of Characters that is based on the underlying file contents.

Throws:

IOException - If reading the file contents denoted by the Path fails.

of

public static Input<Character> of(String name,
 byte[] bytes,
 Charset charset)

Constructs a new Input of Characters on basis of the provided Byte array and Charset.

Parameters:

name - A human-readable name for the Input.

bytes - The underlying source for this Input.

charset - The Charset that shall be used to decode the Byte array.

Returns:

An Input of Characters that is based on the underlying Byte array.

of

public static Input<Character> of(String name,
 CharSequence sequence)

Constructs a new Input of Characters on basis of the provided CharSequence.

Parameters:

name - A human-readable name for the Input.

sequence - The underlying source for this Input.

Returns:

An Input of Characters that is based on the underlying CharSequence.