Class TagChunk

java.lang.Object

org.antlr.v4.runtime.tree.pattern.Chunk

org.antlr.v4.runtime.tree.pattern.TagChunk

class TagChunk
extends Chunk

Represents a placeholder tag in a tree pattern. A tag can have any of the following forms.

• expr: An unlabeled placeholder for a parser rule expr.
• ID: An unlabeled placeholder for a token of type ID.
• e:expr: A labeled placeholder for a parser rule expr.
• id:ID: A labeled placeholder for a token of type ID.

This class does not perform any validation on the tag or label names aside from ensuring that the tag is a non-null, non-empty string.

Field Summary

Fields

Modifier and Type	Field	Description
private final String	label	This is the backing field for getLabel().
private final String	tag	This is the backing field for getTag().

Constructor Summary

Constructors

Constructor	Description
TagChunk(String tag)	Construct a new instance of TagChunk using the specified tag and no label.
TagChunk(String label, String tag)	Construct a new instance of TagChunk using the specified label and tag.

Method Summary

Modifier and Type	Method	Description
final String	getLabel()	Get the label, if any, assigned to this chunk.
final String	getTag()	Get the tag for this chunk.
String	toString()	This method returns a text representation of the tag chunk.

Methods inherited from class Object

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

Field Details

tag

private final String tag

This is the backing field for getTag().

label

private final String label

This is the backing field for getLabel().

Constructor Details

TagChunk

public TagChunk(String tag)

Construct a new instance of TagChunk using the specified tag and no label.

Parameters:

tag - The tag, which should be the name of a parser rule or token type.

Throws:

IllegalArgumentException - if tag is null or empty.

TagChunk

public TagChunk(String label,
 String tag)

Construct a new instance of TagChunk using the specified label and tag.

Parameters:

label - The label for the tag. If this is null, the TagChunk represents an unlabeled tag.

tag - The tag, which should be the name of a parser rule or token type.

Throws:

IllegalArgumentException - if tag is null or empty.

Method Details

getTag

public final String getTag()

Get the tag for this chunk.

Returns:

The tag for the chunk.

getLabel

public final String getLabel()

Get the label, if any, assigned to this chunk.

Returns:

The label assigned to this chunk, or null if no label is assigned to the chunk.

toString

public String toString()

This method returns a text representation of the tag chunk. Labeled tags are returned in the form label:tag, and unlabeled tags are returned as just the tag name.

Overrides:

toString in class Object