Package de.captaingoldfish.scim.sdk.server.filter.antlr

Class FilterVisitor

java.lang.Object

org.antlr.v4.runtime.tree.AbstractParseTreeVisitor<T>

de.captaingoldfish.scim.sdk.server.filter.antlr.ScimFilterBaseVisitor<FilterNode>

de.captaingoldfish.scim.sdk.server.filter.antlr.FilterVisitor

All Implemented Interfaces:

ScimFilterVisitor<FilterNode>, org.antlr.v4.runtime.tree.ParseTreeVisitor<FilterNode>

public class FilterVisitor
extends ScimFilterBaseVisitor<FilterNode>

author Pascal Knueppel
created at: 16.10.2019 - 12:09

The FilterVisitor iterates through the parsed SCIM-filter-tree and calls the here overridden methods for the specific nodes that have been visited.
This visitor will then build its own tree consisting of FilterNodes that will hold all necessary informations about the filter expression

Constructor Summary

Constructors

Constructor	Description
FilterVisitor(ResourceType resourceType)

Method Summary

Modifier and Type	Method	Description
FilterNode	visitAndExpression(ScimFilterParser.AndExpressionContext ctx)	builds an AndExpressionNode
FilterNode	visitAttributeExpression(ScimFilterParser.AttributeExpressionContext ctx)	builds a leaf node in the tree.
FilterNode	visitNotExpression(ScimFilterParser.NotExpressionContext ctx)	builds a NotExpressionNode
FilterNode	visitOrExpression(ScimFilterParser.OrExpressionContext ctx)	builds an OrExpressionNode
FilterNode	visitParenthesisExpression(ScimFilterParser.ParenthesisExpressionContext ctx)	ignores this node and proceeds with the child of this node.
FilterNode	visitValuePath(ScimFilterParser.ValuePathContext ctx)	will resolve a value path that is representing a bracket filter notation

Methods inherited from class de.captaingoldfish.scim.sdk.server.filter.antlr.ScimFilterBaseVisitor

visitAttrExpression, visitAttributePath, visitCompareOperator, visitCompareValue, visitValuePathExpression

Methods inherited from class org.antlr.v4.runtime.tree.AbstractParseTreeVisitor

aggregateResult, defaultResult, shouldVisitNextChild, visit, visitChildren, visitErrorNode, visitTerminal

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.antlr.v4.runtime.tree.ParseTreeVisitor

visit, visitChildren, visitErrorNode, visitTerminal

Constructor Details

FilterVisitor

public FilterVisitor(ResourceType resourceType)

Method Details

visitNotExpression

public FilterNode visitNotExpression(ScimFilterParser.NotExpressionContext ctx)

builds a NotExpressionNode

Specified by:

visitNotExpression in interface ScimFilterVisitor<FilterNode>

Overrides:

visitNotExpression in class ScimFilterBaseVisitor<FilterNode>

Parameters:

ctx - the parsing context from antlr

Returns:

a NotExpressionNode that contains the FilterNode that should be negated

visitOrExpression

public FilterNode visitOrExpression(ScimFilterParser.OrExpressionContext ctx)

builds an OrExpressionNode

Specified by:

visitOrExpression in interface ScimFilterVisitor<FilterNode>

Overrides:

visitOrExpression in class ScimFilterBaseVisitor<FilterNode>

Parameters:

ctx - the parsing context from antlr

Returns:

an OrExpressionNode that contains the left and the right FilterNode the expression

visitAndExpression

public FilterNode visitAndExpression(ScimFilterParser.AndExpressionContext ctx)

builds an AndExpressionNode

Specified by:

visitAndExpression in interface ScimFilterVisitor<FilterNode>

Overrides:

visitAndExpression in class ScimFilterBaseVisitor<FilterNode>

Parameters:

ctx - the parsing context from antlr

Returns:

an AndExpressionNode that contains the left and the right FilterNode the expression

visitParenthesisExpression

public FilterNode visitParenthesisExpression(ScimFilterParser.ParenthesisExpressionContext ctx)

ignores this node and proceeds with the child of this node. We do not need to evaluate the parenthesis directly because this is implicitly done by antlr in the way the tree is build

Specified by:

visitParenthesisExpression in interface ScimFilterVisitor<FilterNode>

Overrides:

visitParenthesisExpression in class ScimFilterBaseVisitor<FilterNode>

Parameters:

ctx - the parsing context from antlr

Returns:

a FilterNode that might be any other FilterNode implementation

visitAttributeExpression

public FilterNode visitAttributeExpression(ScimFilterParser.AttributeExpressionContext ctx)

builds a leaf node in the tree. The leaf nodes do contain all necessary data to evaluate the filter and to use them to build jpa predicates for example

Specified by:

visitAttributeExpression in interface ScimFilterVisitor<FilterNode>

Overrides:

visitAttributeExpression in class ScimFilterBaseVisitor<FilterNode>

Parameters:

ctx - the parsing context from antlr

Returns:

an AttributeExpressionLeaf that does contain all necessary data and meta-data

visitValuePath

public FilterNode visitValuePath(ScimFilterParser.ValuePathContext ctx)

will resolve a value path that is representing a bracket filter notation

Specified by:

visitValuePath in interface ScimFilterVisitor<FilterNode>

Overrides:

visitValuePath in class ScimFilterBaseVisitor<FilterNode>

Parameters:

ctx - the parsing context from antlr

Returns:

resolves the bracket notation into a normal filter expression