/**
* BSD-style license; for more info see http://pmd.sourceforge.net/license.html
*/
package net.sourceforge.pmd.lang.java.rule.optimizations;
import net.sourceforge.pmd.lang.ast.Node;
import net.sourceforge.pmd.lang.java.ast.ASTArgumentList;
import net.sourceforge.pmd.lang.java.ast.ASTAssignmentOperator;
import net.sourceforge.pmd.lang.java.ast.ASTConditionalExpression;
import net.sourceforge.pmd.lang.java.ast.ASTEqualityExpression;
import net.sourceforge.pmd.lang.java.ast.ASTLocalVariableDeclaration;
import net.sourceforge.pmd.lang.java.ast.ASTName;
import net.sourceforge.pmd.lang.java.ast.ASTPrimaryExpression;
import net.sourceforge.pmd.lang.java.ast.ASTStatementExpression;
import net.sourceforge.pmd.lang.java.ast.ASTVariableDeclaratorId;
import net.sourceforge.pmd.lang.java.rule.AbstractJavaRule;
import net.sourceforge.pmd.lang.java.typeresolution.TypeHelper;
import net.sourceforge.pmd.lang.symboltable.NameOccurrence;
public class UseStringBufferForStringAppendsRule extends AbstractJavaRule {
@Override
public Object visit(ASTVariableDeclaratorId node, Object data) {
if (!TypeHelper.isA(node, String.class) || node.isArray()) {
return data;
}
Node parent = node.jjtGetParent().jjtGetParent();
if (!(parent instanceof ASTLocalVariableDeclaration)) {
return data;
}
for (NameOccurrence no : node.getUsages()) {
Node name = no.getLocation();
ASTStatementExpression statement = name.getFirstParentOfType(ASTStatementExpression.class);
if (statement == null) {
continue;
}
ASTArgumentList argList = name.getFirstParentOfType(ASTArgumentList.class);
if (argList != null && argList.getFirstParentOfType(ASTStatementExpression.class) == statement) {
// used in method call
continue;
}
ASTEqualityExpression equality = name.getFirstParentOfType(ASTEqualityExpression.class);
if (equality != null && equality.getFirstParentOfType(ASTStatementExpression.class) == statement) {
// used in condition
continue;
}
ASTConditionalExpression conditional = name.getFirstParentOfType(ASTConditionalExpression.class);
if (conditional != null) {
Node thirdParent = name.jjtGetParent().jjtGetParent().jjtGetParent();
if ((thirdParent == conditional || thirdParent.jjtGetParent() == conditional)
&& conditional.getFirstParentOfType(ASTStatementExpression.class) == statement) {
// is used in ternary as only option (not appended to other
// string)
continue;
}
}
if (statement.jjtGetNumChildren() > 0 && statement.jjtGetChild(0) instanceof ASTPrimaryExpression) {
ASTName astName = statement.jjtGetChild(0).getFirstDescendantOfType(ASTName.class);
if (astName != null) {
if (astName.equals(name)) {
ASTAssignmentOperator assignmentOperator = statement
.getFirstDescendantOfType(ASTAssignmentOperator.class);
if (assignmentOperator != null && assignmentOperator.isCompound()) {
addViolation(data, assignmentOperator);
}
} else if (astName.getImage().equals(name.getImage())) {
ASTAssignmentOperator assignmentOperator = statement
.getFirstDescendantOfType(ASTAssignmentOperator.class);
if (assignmentOperator != null && !assignmentOperator.isCompound()) {
addViolation(data, astName);
}
}
}
}
}
return data;
}
}