LexicalDifferenceCalculator.java
/*
* Copyright (C) 2007-2010 J��lio Vilmar Gesser.
* Copyright (C) 2011, 2013-2023 The JavaParser Team.
*
* This file is part of JavaParser.
*
* JavaParser can be used either under the terms of
* a) the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
* b) the terms of the Apache License
*
* You should have received a copy of both licenses in LICENCE.LGPL and
* LICENCE.APACHE. Please refer to those files for details.
*
* JavaParser is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*/
package com.github.javaparser.printer.lexicalpreservation;
import java.util.*;
import com.github.javaparser.GeneratedJavaParserConstants;
import com.github.javaparser.ast.Modifier;
import com.github.javaparser.ast.Node;
import com.github.javaparser.ast.NodeList;
import com.github.javaparser.ast.expr.CharLiteralExpr;
import com.github.javaparser.ast.expr.LambdaExpr;
import com.github.javaparser.ast.expr.StringLiteralExpr;
import com.github.javaparser.ast.expr.TextBlockLiteralExpr;
import com.github.javaparser.ast.observer.ObservableProperty;
import com.github.javaparser.ast.stmt.ExpressionStmt;
import com.github.javaparser.printer.ConcreteSyntaxModel;
import com.github.javaparser.printer.SourcePrinter;
import com.github.javaparser.printer.Stringable;
import com.github.javaparser.printer.concretesyntaxmodel.*;
import com.github.javaparser.printer.lexicalpreservation.changes.*;
import com.github.javaparser.utils.LineSeparator;
class LexicalDifferenceCalculator {
/**
* The ConcreteSyntaxModel represents the general format. This model is a calculated version of the ConcreteSyntaxModel,
* with no condition, no lists, just tokens and node children.
*/
static class CalculatedSyntaxModel {
final List<CsmElement> elements;
CalculatedSyntaxModel(List<CsmElement> elements) {
this.elements = elements;
}
public CalculatedSyntaxModel from(int index) {
return new CalculatedSyntaxModel(new ArrayList<>(elements.subList(index, elements.size())));
}
@Override
public String toString() {
return "CalculatedSyntaxModel{" + "elements=" + elements + '}';
}
CalculatedSyntaxModel sub(int start, int end) {
return new CalculatedSyntaxModel(elements.subList(start, end));
}
void removeIndentationElements() {
elements.removeIf(el -> el instanceof CsmIndent || el instanceof CsmUnindent);
}
}
public static class CsmChild implements CsmElement {
private final Node child;
public Node getChild() {
return child;
}
CsmChild(Node child) {
this.child = child;
}
@Override
public void prettyPrint(Node node, SourcePrinter printer) {
throw new UnsupportedOperationException();
}
/*
* Verifies if the content of the {@code CsmElement} is the same as the provided {@code TextElement}
*/
@Override
public boolean isCorrespondingElement(TextElement textElement) {
return (textElement instanceof ChildTextElement)
&& ((ChildTextElement)textElement).getChild() == getChild();
}
@Override
public String toString() {
return "child(" + child.getClass().getSimpleName() + ")";
}
@Override
public boolean equals(Object o) {
if (this == o)
return true;
if (o == null || getClass() != o.getClass())
return false;
CsmChild csmChild = (CsmChild) o;
return child.equals(csmChild.child);
}
@Override
public int hashCode() {
return child.hashCode();
}
}
List<DifferenceElement> calculateListRemovalDifference(ObservableProperty observableProperty, NodeList<?> nodeList, int index) {
Node container = nodeList.getParentNodeForChildren();
CsmElement element = ConcreteSyntaxModel.forClass(container.getClass());
CalculatedSyntaxModel original = calculatedSyntaxModelForNode(element, container);
CalculatedSyntaxModel after = calculatedSyntaxModelAfterListRemoval(element, observableProperty, nodeList, index);
return DifferenceElementCalculator.calculate(original, after);
}
List<DifferenceElement> calculateListAdditionDifference(ObservableProperty observableProperty, NodeList<?> nodeList, int index, Node nodeAdded) {
Node container = nodeList.getParentNodeForChildren();
CsmElement element = ConcreteSyntaxModel.forClass(container.getClass());
CalculatedSyntaxModel original = calculatedSyntaxModelForNode(element, container);
CalculatedSyntaxModel after = calculatedSyntaxModelAfterListAddition(element, observableProperty, nodeList, index, nodeAdded);
List<DifferenceElement> differenceElements = DifferenceElementCalculator.calculate(original, after);
// Set the line separator character tokens
LineSeparator lineSeparator = container.getLineEndingStyleOrDefault(LineSeparator.SYSTEM);
replaceEolTokens(differenceElements, lineSeparator);
return differenceElements;
}
/*
* Replace EOL token in the list of {@code DifferenceElement} by the specified line separator
*/
private void replaceEolTokens(List<DifferenceElement> differenceElements, LineSeparator lineSeparator) {
CsmElement eol = getNewLineToken(lineSeparator);
for (int i = 0; i < differenceElements.size(); i++) {
DifferenceElement differenceElement = differenceElements.get(i);
differenceElements.set(i, differenceElement.replaceEolTokens(eol));
}
}
/*
* Returns a new line token
*/
private CsmElement getNewLineToken(LineSeparator lineSeparator) {
return CsmElement.newline(lineSeparator);
}
List<DifferenceElement> calculateListReplacementDifference(ObservableProperty observableProperty, NodeList<?> nodeList, int index, Node newValue) {
Node container = nodeList.getParentNodeForChildren();
CsmElement element = ConcreteSyntaxModel.forClass(container.getClass());
CalculatedSyntaxModel original = calculatedSyntaxModelForNode(element, container);
CalculatedSyntaxModel after = calculatedSyntaxModelAfterListReplacement(element, observableProperty, nodeList, index, newValue);
return DifferenceElementCalculator.calculate(original, after);
}
void calculatePropertyChange(NodeText nodeText, Node observedNode, ObservableProperty property, Object oldValue, Object newValue) {
if (nodeText == null) {
throw new NullPointerException();
}
CsmElement element = ConcreteSyntaxModel.forClass(observedNode.getClass());
CalculatedSyntaxModel original = calculatedSyntaxModelForNode(element, observedNode);
CalculatedSyntaxModel after = calculatedSyntaxModelAfterPropertyChange(element, observedNode, property, oldValue, newValue);
List<DifferenceElement> differenceElements = DifferenceElementCalculator.calculate(original, after);
Difference difference = new Difference(differenceElements, nodeText, observedNode);
difference.apply();
}
// Visible for testing
CalculatedSyntaxModel calculatedSyntaxModelForNode(CsmElement csm, Node node) {
List<CsmElement> elements = new LinkedList<>();
calculatedSyntaxModelForNode(csm, node, elements, new NoChange());
return new CalculatedSyntaxModel(elements);
}
CalculatedSyntaxModel calculatedSyntaxModelForNode(Node node) {
return calculatedSyntaxModelForNode(ConcreteSyntaxModel.forClass(node.getClass()), node);
}
private void calculatedSyntaxModelForNode(CsmElement csm, Node node, List<CsmElement> elements, Change change) {
if (csm instanceof CsmSequence) {
CsmSequence csmSequence = (CsmSequence) csm;
csmSequence.getElements().forEach(e -> calculatedSyntaxModelForNode(e, node, elements, change));
} else if (csm instanceof CsmComment) {
// nothing to do
} else if (csm instanceof CsmSingleReference) {
CsmSingleReference csmSingleReference = (CsmSingleReference) csm;
Node child;
if (change instanceof PropertyChange && ((PropertyChange) change).getProperty() == csmSingleReference.getProperty()) {
child = (Node) ((PropertyChange) change).getNewValue();
if (node instanceof LambdaExpr && child instanceof ExpressionStmt) {
// Same edge-case as in DefaultPrettyPrinterVisitor.visit(LambdaExpr, Void)
child = ((ExpressionStmt) child).getExpression();
}
} else {
child = csmSingleReference.getProperty().getValueAsSingleReference(node);
}
if (child != null) {
elements.add(new CsmChild(child));
}
} else if (csm instanceof CsmNone) {
// nothing to do
} else if (csm instanceof CsmToken) {
elements.add(csm);
} else if (csm instanceof CsmOrphanCommentsEnding) {
// nothing to do
} else if (csm instanceof CsmList) {
CsmList csmList = (CsmList) csm;
if (csmList.getProperty().isAboutNodes()) {
Object rawValue = change.getValue(csmList.getProperty(), node);
NodeList<?> nodeList;
if (rawValue instanceof Optional) {
Optional<?> optional = (Optional<?>) rawValue;
if (optional.isPresent()) {
if (!(optional.get() instanceof NodeList)) {
throw new IllegalStateException("Expected NodeList, found " + optional.get().getClass().getCanonicalName());
}
nodeList = (NodeList<?>) optional.get();
} else {
nodeList = new NodeList<>();
}
} else {
if (!(rawValue instanceof NodeList)) {
throw new IllegalStateException("Expected NodeList, found " + rawValue.getClass().getCanonicalName());
}
nodeList = (NodeList<?>) rawValue;
}
if (!nodeList.isEmpty()) {
calculatedSyntaxModelForNode(csmList.getPreceeding(), node, elements, change);
for (int i = 0; i < nodeList.size(); i++) {
if (i != 0) {
calculatedSyntaxModelForNode(csmList.getSeparatorPre(), node, elements, change);
}
elements.add(new CsmChild(nodeList.get(i)));
if (i != (nodeList.size() - 1)) {
calculatedSyntaxModelForNode(csmList.getSeparatorPost(), node, elements, change);
}
}
calculatedSyntaxModelForNode(csmList.getFollowing(), node, elements, change);
}
} else {
Collection<?> collection = (Collection<?>) change.getValue(csmList.getProperty(), node);
if (!collection.isEmpty()) {
calculatedSyntaxModelForNode(csmList.getPreceeding(), node, elements, change);
boolean first = true;
for (Iterator<?> it = collection.iterator(); it.hasNext(); ) {
if (!first) {
calculatedSyntaxModelForNode(csmList.getSeparatorPre(), node, elements, change);
}
Object value = it.next();
if (value instanceof Modifier) {
Modifier modifier = (Modifier) value;
elements.add(new CsmToken(toToken(modifier)));
} else {
throw new UnsupportedOperationException(it.next().getClass().getSimpleName());
}
if (it.hasNext()) {
calculatedSyntaxModelForNode(csmList.getSeparatorPost(), node, elements, change);
}
first = false;
}
calculatedSyntaxModelForNode(csmList.getFollowing(), node, elements, change);
}
}
} else if (csm instanceof CsmConditional) {
CsmConditional csmConditional = (CsmConditional) csm;
boolean satisfied = change.evaluate(csmConditional, node);
if (satisfied) {
calculatedSyntaxModelForNode(csmConditional.getThenElement(), node, elements, change);
} else {
calculatedSyntaxModelForNode(csmConditional.getElseElement(), node, elements, change);
}
} else if (csm instanceof CsmIndent) {
elements.add(csm);
} else if (csm instanceof CsmUnindent) {
elements.add(csm);
} else if (csm instanceof CsmAttribute) {
CsmAttribute csmAttribute = (CsmAttribute) csm;
Object value = change.getValue(csmAttribute.getProperty(), node);
String text = value.toString();
if (value instanceof Stringable) {
text = ((Stringable) value).asString();
}
elements.add(new CsmToken(csmAttribute.getTokenType(node, value.toString(), text), text));
} else if ((csm instanceof CsmString) && (node instanceof StringLiteralExpr)) {
// fix #2382:
// This method calculates the syntax model _after_ the change has been applied.
// If the given change is a PropertyChange, the returned model should
// contain the new value, otherwise the original/current value should be used.
if (change instanceof PropertyChange) {
elements.add(new CsmToken(GeneratedJavaParserConstants.STRING_LITERAL, "\"" + ((PropertyChange) change).getNewValue() + "\""));
} else {
elements.add(new CsmToken(GeneratedJavaParserConstants.STRING_LITERAL, "\"" + ((StringLiteralExpr) node).getValue() + "\""));
}
} else if ((csm instanceof CsmString) && (node instanceof TextBlockLiteralExpr)) {
// Per https://openjdk.java.net/jeps/378#1--Line-terminators, any 'CRLF' and 'CR' are turned into 'LF' before interpreting the text
String eol = node.getLineEndingStyle().toString();
// FIXME: csm should be CsmTextBlock -- See also #2677
if (change instanceof PropertyChange) {
elements.add(new CsmToken(GeneratedJavaParserConstants.TEXT_BLOCK_LITERAL, "\"\"\"" + eol + ((PropertyChange) change).getNewValue() + "\"\"\""));
} else {
elements.add(new CsmToken(GeneratedJavaParserConstants.TEXT_BLOCK_LITERAL, "\"\"\"" + eol + ((TextBlockLiteralExpr) node).getValue() + "\"\"\""));
}
} else if ((csm instanceof CsmChar) && (node instanceof CharLiteralExpr)) {
if (change instanceof PropertyChange) {
elements.add(new CsmToken(GeneratedJavaParserConstants.CHAR, "'" + ((PropertyChange) change).getNewValue() + "'"));
} else {
elements.add(new CsmToken(GeneratedJavaParserConstants.CHAR, "'" + ((CharLiteralExpr) node).getValue() + "'"));
}
} else if (csm instanceof CsmMix) {
CsmMix csmMix = (CsmMix) csm;
List<CsmElement> mixElements = new LinkedList<>();
csmMix.getElements().forEach(e -> calculatedSyntaxModelForNode(e, node, mixElements, change));
elements.add(new CsmMix(mixElements));
} else if (csm instanceof CsmChild) {
elements.add(csm);
} else {
throw new UnsupportedOperationException(csm.getClass().getSimpleName() + " " + csm);
}
}
public static int toToken(Modifier modifier) {
switch(modifier.getKeyword()) {
case PUBLIC:
return GeneratedJavaParserConstants.PUBLIC;
case PRIVATE:
return GeneratedJavaParserConstants.PRIVATE;
case PROTECTED:
return GeneratedJavaParserConstants.PROTECTED;
case STATIC:
return GeneratedJavaParserConstants.STATIC;
case FINAL:
return GeneratedJavaParserConstants.FINAL;
case ABSTRACT:
return GeneratedJavaParserConstants.ABSTRACT;
case TRANSIENT:
return GeneratedJavaParserConstants.TRANSIENT;
case SYNCHRONIZED:
return GeneratedJavaParserConstants.SYNCHRONIZED;
case VOLATILE:
return GeneratedJavaParserConstants.VOLATILE;
case NATIVE:
return GeneratedJavaParserConstants.NATIVE;
case STRICTFP:
return GeneratedJavaParserConstants.STRICTFP;
case TRANSITIVE:
return GeneratedJavaParserConstants.TRANSITIVE;
default:
throw new UnsupportedOperationException(modifier.getKeyword().name());
}
}
// /
// / Methods that calculate CalculatedSyntaxModel
// /
// Visible for testing
CalculatedSyntaxModel calculatedSyntaxModelAfterPropertyChange(Node node, ObservableProperty property, Object oldValue, Object newValue) {
return calculatedSyntaxModelAfterPropertyChange(ConcreteSyntaxModel.forClass(node.getClass()), node, property, oldValue, newValue);
}
// Visible for testing
CalculatedSyntaxModel calculatedSyntaxModelAfterPropertyChange(CsmElement csm, Node node, ObservableProperty property, Object oldValue, Object newValue) {
List<CsmElement> elements = new LinkedList<>();
calculatedSyntaxModelForNode(csm, node, elements, new PropertyChange(property, oldValue, newValue));
return new CalculatedSyntaxModel(elements);
}
// Visible for testing
CalculatedSyntaxModel calculatedSyntaxModelAfterListRemoval(CsmElement csm, ObservableProperty observableProperty, NodeList<?> nodeList, int index) {
List<CsmElement> elements = new LinkedList<>();
Node container = nodeList.getParentNodeForChildren();
calculatedSyntaxModelForNode(csm, container, elements, new ListRemovalChange(observableProperty, index));
return new CalculatedSyntaxModel(elements);
}
// Visible for testing
CalculatedSyntaxModel calculatedSyntaxModelAfterListAddition(CsmElement csm, ObservableProperty observableProperty, NodeList<?> nodeList, int index, Node nodeAdded) {
List<CsmElement> elements = new LinkedList<>();
Node container = nodeList.getParentNodeForChildren();
calculatedSyntaxModelForNode(csm, container, elements, new ListAdditionChange(observableProperty, index, nodeAdded));
return new CalculatedSyntaxModel(elements);
}
// Visible for testing
CalculatedSyntaxModel calculatedSyntaxModelAfterListAddition(Node container, ObservableProperty observableProperty, int index, Node nodeAdded) {
CsmElement csm = ConcreteSyntaxModel.forClass(container.getClass());
Object rawValue = observableProperty.getRawValue(container);
if (!(rawValue instanceof NodeList)) {
throw new IllegalStateException("Expected NodeList, found " + rawValue.getClass().getCanonicalName());
}
NodeList<?> nodeList = (NodeList<?>) rawValue;
return calculatedSyntaxModelAfterListAddition(csm, observableProperty, nodeList, index, nodeAdded);
}
// Visible for testing
CalculatedSyntaxModel calculatedSyntaxModelAfterListRemoval(Node container, ObservableProperty observableProperty, int index) {
CsmElement csm = ConcreteSyntaxModel.forClass(container.getClass());
Object rawValue = observableProperty.getRawValue(container);
if (!(rawValue instanceof NodeList)) {
throw new IllegalStateException("Expected NodeList, found " + rawValue.getClass().getCanonicalName());
}
NodeList<?> nodeList = (NodeList<?>) rawValue;
return calculatedSyntaxModelAfterListRemoval(csm, observableProperty, nodeList, index);
}
// Visible for testing
private CalculatedSyntaxModel calculatedSyntaxModelAfterListReplacement(CsmElement csm, ObservableProperty observableProperty, NodeList<?> nodeList, int index, Node newValue) {
List<CsmElement> elements = new LinkedList<>();
Node container = nodeList.getParentNodeForChildren();
calculatedSyntaxModelForNode(csm, container, elements, new ListReplacementChange(observableProperty, index, newValue));
return new CalculatedSyntaxModel(elements);
}
}