Package org.antlr.v4.runtime.tree.pattern

Class ParseTreeMatch

java.lang.Object

org.antlr.v4.runtime.tree.pattern.ParseTreeMatch

public class ParseTreeMatch
extends Object

Represents the result of matching a ParseTree against a tree pattern.

Constructor Summary

Constructors

Constructor	Description
ParseTreeMatch(ParseTree tree, ParseTreePattern pattern, MultiMap<String,ParseTree> labels, ParseTree mismatchedNode)	Constructs a new instance of ParseTreeMatch from the specified parse tree and pattern.

Method Summary

Modifier and Type	Method	Description
ParseTree	get(String label)	Get the last node associated with a specific label.
List<ParseTree>	getAll(String label)	Return all nodes matching a rule or token tag with the specified label.
MultiMap<String,ParseTree>	getLabels()	Return a mapping from label → [list of nodes].
ParseTree	getMismatchedNode()	Get the node at which we first detected a mismatch.
ParseTreePattern	getPattern()	Get the tree pattern we are matching against.
ParseTree	getTree()	Get the parse tree we are trying to match to a pattern.
boolean	succeeded()	Gets a value indicating whether the match operation succeeded.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

ParseTreeMatch

public ParseTreeMatch(ParseTree tree,
                      ParseTreePattern pattern,
                      MultiMap<String,ParseTree> labels,
                      ParseTree mismatchedNode)

Constructs a new instance of ParseTreeMatch from the specified parse tree and pattern.

Parameters:

tree - The parse tree to match against the pattern.

pattern - The parse tree pattern.

labels - A mapping from label names to collections of ParseTree objects located by the tree pattern matching process.

mismatchedNode - The first node which failed to match the tree pattern during the matching process.

Throws:

IllegalArgumentException - if tree is null

IllegalArgumentException - if pattern is null

IllegalArgumentException - if labels is null

Method Detail

get

public ParseTree get(String label)

Get the last node associated with a specific label.

For example, for pattern <id:ID>, get("id") returns the node matched for that ID. If more than one node matched the specified label, only the last is returned. If there is no node associated with the label, this returns null.

Pattern tags like <ID> and <expr> without labels are considered to be labeled with ID and expr, respectively.

Parameters:

label - The label to check.

Returns:

The last ParseTree to match a tag with the specified label, or null if no parse tree matched a tag with the label.

getAll

public List<ParseTree> getAll(String label)

Return all nodes matching a rule or token tag with the specified label.

If the label is the name of a parser rule or token in the grammar, the resulting list will contain both the parse trees matching rule or tags explicitly labeled with the label and the complete set of parse trees matching the labeled and unlabeled tags in the pattern for the parser rule or token. For example, if label is "foo", the result will contain all of the following.

• Parse tree nodes matching tags of the form <foo:anyRuleName> and <foo:AnyTokenName>.
• Parse tree nodes matching tags of the form <anyLabel:foo>.
• Parse tree nodes matching tags of the form <foo>.

Parameters:

label - The label.

Returns:

A collection of all ParseTree nodes matching tags with the specified label. If no nodes matched the label, an empty list is returned.

getLabels

public MultiMap<String,ParseTree> getLabels()

Return a mapping from label → [list of nodes].

The map includes special entries corresponding to the names of rules and tokens referenced in tags in the original pattern. For additional information, see the description of getAll(String).

Returns:

A mapping from labels to parse tree nodes. If the parse tree pattern did not contain any rule or token tags, this map will be empty.

getMismatchedNode

public ParseTree getMismatchedNode()

Get the node at which we first detected a mismatch.

Returns:

the node at which we first detected a mismatch, or null if the match was successful.

succeeded

public boolean succeeded()

Gets a value indicating whether the match operation succeeded.

Returns:

true if the match operation succeeded; otherwise, false.

getPattern

public ParseTreePattern getPattern()

Get the tree pattern we are matching against.

Returns:

The tree pattern we are matching against.

getTree

public ParseTree getTree()

Get the parse tree we are trying to match to a pattern.

Returns:

The ParseTree we are trying to match to a pattern.

toString

public String toString()

Overrides:

toString in class Object