/*
* SonarQube Java
* Copyright (C) 2012-2016 SonarSource SA
* mailto:contact AT sonarsource DOT com
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of 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.
*
* This program 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.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
package org.sonar.java.se.constraint;
import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableList;
import org.sonar.java.se.Pair;
import org.sonar.java.se.ProgramState;
import org.sonar.java.se.SymbolicValueFactory;
import org.sonar.java.se.symbolicvalues.NullCheckSymbolicValue;
import org.sonar.java.se.symbolicvalues.RelationalSymbolicValue;
import org.sonar.java.se.symbolicvalues.SymbolicValue;
import org.sonar.plugins.java.api.semantic.Symbol;
import org.sonar.plugins.java.api.semantic.Type;
import org.sonar.plugins.java.api.tree.ExpressionTree;
import org.sonar.plugins.java.api.tree.IdentifierTree;
import org.sonar.plugins.java.api.tree.MemberSelectExpressionTree;
import org.sonar.plugins.java.api.tree.MethodInvocationTree;
import org.sonar.plugins.java.api.tree.Tree;
import javax.annotation.Nullable;
import java.util.List;
public class ConstraintManager {
private int counter = ProgramState.EMPTY_STATE.constraintsSize();
private SymbolicValueFactory symbolicValueFactory;
public void setValueFactory(SymbolicValueFactory valueFactory) {
Preconditions.checkState(symbolicValueFactory == null, "The symbolic value factory has already been defined by another checker!");
symbolicValueFactory = valueFactory;
}
public SymbolicValue createSymbolicValue(Tree syntaxNode) {
SymbolicValue result;
switch (syntaxNode.kind()) {
case EQUAL_TO:
result = new RelationalSymbolicValue(counter, RelationalSymbolicValue.Kind.EQUAL);
break;
case NOT_EQUAL_TO:
result = new RelationalSymbolicValue(counter, RelationalSymbolicValue.Kind.NOT_EQUAL);
break;
case LESS_THAN:
result = new RelationalSymbolicValue(counter, RelationalSymbolicValue.Kind.LESS_THAN);
break;
case LESS_THAN_OR_EQUAL_TO:
result = new RelationalSymbolicValue(counter, RelationalSymbolicValue.Kind.LESS_THAN_OR_EQUAL);
break;
case GREATER_THAN:
result = new RelationalSymbolicValue(counter, RelationalSymbolicValue.Kind.GREATER_THAN);
break;
case GREATER_THAN_OR_EQUAL_TO:
result = new RelationalSymbolicValue(counter, RelationalSymbolicValue.Kind.GREATER_THAN_OR_EQUAL);
break;
case LOGICAL_COMPLEMENT:
result = new SymbolicValue.NotSymbolicValue(counter);
break;
case AND:
case AND_ASSIGNMENT:
result = new SymbolicValue.AndSymbolicValue(counter);
break;
case OR:
case OR_ASSIGNMENT:
result = new SymbolicValue.OrSymbolicValue(counter);
break;
case XOR:
case XOR_ASSIGNMENT:
result = new SymbolicValue.XorSymbolicValue(counter);
break;
case INSTANCE_OF:
result = new SymbolicValue.InstanceOfSymbolicValue(counter);
break;
case MEMBER_SELECT:
result = createIdentifierSymbolicValue(((MemberSelectExpressionTree) syntaxNode).identifier());
break;
case IDENTIFIER:
result = createIdentifierSymbolicValue((IdentifierTree) syntaxNode);
break;
default:
result = createDefaultSymbolicValue();
}
counter++;
return result;
}
public SymbolicValue.ExceptionalSymbolicValue createExceptionalSymbolicValue(@Nullable Type exceptionType) {
SymbolicValue.ExceptionalSymbolicValue result = new SymbolicValue.ExceptionalSymbolicValue(counter, exceptionType);
counter++;
return result;
}
public SymbolicValue createMethodSymbolicValue(MethodInvocationTree syntaxNode, List<SymbolicValue> values) {
SymbolicValue result;
if (isEqualsMethod(syntaxNode) || isObjectsMethod(syntaxNode.symbol(), "equals")) {
result = new RelationalSymbolicValue(counter, RelationalSymbolicValue.Kind.METHOD_EQUALS);
SymbolicValue leftOp = values.get(1);
SymbolicValue rightOp = values.get(0);
result.computedFrom(ImmutableList.of(rightOp, leftOp));
} else if (isObjectsMethod(syntaxNode.symbol(), "isNull")) {
result = new NullCheckSymbolicValue(counter, true);
SymbolicValue operand = values.get(0);
result.computedFrom(ImmutableList.of(operand));
} else if (isObjectsMethod(syntaxNode.symbol(), "nonNull")) {
result = new NullCheckSymbolicValue(counter, false);
SymbolicValue operand = values.get(0);
result.computedFrom(ImmutableList.of(operand));
} else {
result = createDefaultSymbolicValue();
}
counter++;
return result;
}
private static boolean isObjectsMethod(Symbol symbol, String methodName) {
return symbol.isMethodSymbol() && symbol.owner().type().is("java.util.Objects") && methodName.equals(symbol.name());
}
private static boolean isEqualsMethod(MethodInvocationTree syntaxNode) {
if (syntaxNode.arguments().size() == 1) {
ExpressionTree methodSelect = syntaxNode.methodSelect();
if (methodSelect.is(Tree.Kind.MEMBER_SELECT)) {
MemberSelectExpressionTree expression = (MemberSelectExpressionTree) methodSelect;
if ("equals".equals(expression.identifier().name()) && syntaxNode.symbol().isMethodSymbol()) {
Symbol.MethodSymbol symbol = (Symbol.MethodSymbol) syntaxNode.symbol();
return symbol.parameterTypes().get(0).is("java.lang.Object");
}
}
}
return false;
}
private SymbolicValue createIdentifierSymbolicValue(IdentifierTree identifier) {
final Type type = identifier.symbol().type();
if (type != null && type.is("java.lang.Boolean")) {
if ("TRUE".equals(identifier.name())) {
return SymbolicValue.TRUE_LITERAL;
} else if ("FALSE".equals(identifier.name())) {
return SymbolicValue.FALSE_LITERAL;
}
}
return createDefaultSymbolicValue();
}
private SymbolicValue createDefaultSymbolicValue() {
SymbolicValue result;
result = symbolicValueFactory == null ? new SymbolicValue(counter) : symbolicValueFactory.createSymbolicValue(counter);
symbolicValueFactory = null;
return result;
}
public boolean isNull(ProgramState ps, SymbolicValue val) {
Object constraint = ps.getConstraint(val);
return constraint instanceof ObjectConstraint && ((ObjectConstraint) constraint).isNull();
}
public Pair<List<ProgramState>, List<ProgramState>> assumeDual(ProgramState programState) {
ProgramState.Pop unstack = programState.unstackValue(1);
SymbolicValue sv = unstack.values.get(0);
List<ProgramState> falseConstraint = sv.setConstraint(unstack.state, BooleanConstraint.FALSE);
List<ProgramState> trueConstraint = sv.setConstraint(unstack.state, BooleanConstraint.TRUE);
return new Pair<>(falseConstraint, trueConstraint);
}
}