/**
* BSD-style license; for more info see http://pmd.sourceforge.net/license.html
*/
package net.sourceforge.pmd.lang.java.rule.unusedcode;
import java.io.InvalidObjectException;
import java.io.ObjectInputStream;
import java.util.List;
import java.util.Map;
import net.sourceforge.pmd.lang.ast.Node;
import net.sourceforge.pmd.lang.java.ast.ASTClassOrInterfaceDeclaration;
import net.sourceforge.pmd.lang.java.ast.ASTConstructorDeclaration;
import net.sourceforge.pmd.lang.java.ast.ASTFormalParameter;
import net.sourceforge.pmd.lang.java.ast.ASTMarkerAnnotation;
import net.sourceforge.pmd.lang.java.ast.ASTMethodDeclaration;
import net.sourceforge.pmd.lang.java.ast.ASTMethodDeclarator;
import net.sourceforge.pmd.lang.java.ast.ASTName;
import net.sourceforge.pmd.lang.java.ast.ASTNameList;
import net.sourceforge.pmd.lang.java.ast.ASTType;
import net.sourceforge.pmd.lang.java.ast.JavaNode;
import net.sourceforge.pmd.lang.java.rule.AbstractJavaRule;
import net.sourceforge.pmd.lang.java.symboltable.JavaNameOccurrence;
import net.sourceforge.pmd.lang.java.symboltable.VariableNameDeclaration;
import net.sourceforge.pmd.lang.rule.properties.BooleanProperty;
import net.sourceforge.pmd.lang.symboltable.NameOccurrence;
public class UnusedFormalParameterRule extends AbstractJavaRule {
private static final BooleanProperty CHECKALL_DESCRIPTOR = new BooleanProperty("checkAll",
"Check all methods, including non-private ones", false, 1.0f);
public UnusedFormalParameterRule() {
definePropertyDescriptor(CHECKALL_DESCRIPTOR);
}
public Object visit(ASTConstructorDeclaration node, Object data) {
check(node, data);
return data;
}
public Object visit(ASTMethodDeclaration node, Object data) {
if (!node.isPrivate() && !getProperty(CHECKALL_DESCRIPTOR)) {
return data;
}
if (!node.isNative() && !node.isAbstract() && !isSerializationMethod(node) && !hasOverrideAnnotation(node)) {
check(node, data);
}
return data;
}
private boolean isSerializationMethod(ASTMethodDeclaration node) {
ASTMethodDeclarator declarator = node.getFirstDescendantOfType(ASTMethodDeclarator.class);
List<ASTFormalParameter> parameters = declarator.findDescendantsOfType(ASTFormalParameter.class);
if (node.isPrivate() && "readObject".equals(node.getMethodName()) && parameters.size() == 1
&& throwsOneException(node, InvalidObjectException.class)) {
ASTType type = parameters.get(0).getTypeNode();
if (type.getType() == ObjectInputStream.class
|| ObjectInputStream.class.getSimpleName().equals(type.getTypeImage())
|| ObjectInputStream.class.getName().equals(type.getTypeImage())) {
return true;
}
}
return false;
}
private boolean throwsOneException(ASTMethodDeclaration node, Class<? extends Throwable> exception) {
ASTNameList throwsList = node.getThrows();
if (throwsList != null && throwsList.jjtGetNumChildren() == 1) {
ASTName n = (ASTName) throwsList.jjtGetChild(0);
if (n.getType() == exception || exception.getSimpleName().equals(n.getImage())
|| exception.getName().equals(n.getImage())) {
return true;
}
}
return false;
}
private void check(Node node, Object data) {
Node parent = node.jjtGetParent().jjtGetParent().jjtGetParent();
if (parent instanceof ASTClassOrInterfaceDeclaration
&& !((ASTClassOrInterfaceDeclaration) parent).isInterface()) {
Map<VariableNameDeclaration, List<NameOccurrence>> vars = ((JavaNode) node).getScope()
.getDeclarations(VariableNameDeclaration.class);
for (Map.Entry<VariableNameDeclaration, List<NameOccurrence>> entry : vars.entrySet()) {
VariableNameDeclaration nameDecl = entry.getKey();
if (actuallyUsed(nameDecl, entry.getValue())) {
continue;
}
addViolation(data, nameDecl.getNode(), new Object[] {
node instanceof ASTMethodDeclaration ? "method" : "constructor", nameDecl.getImage(), });
}
}
}
private boolean actuallyUsed(VariableNameDeclaration nameDecl, List<NameOccurrence> usages) {
for (NameOccurrence occ : usages) {
JavaNameOccurrence jocc = (JavaNameOccurrence) occ;
if (jocc.isOnLeftHandSide()) {
if (nameDecl.isArray() && jocc.getLocation().jjtGetParent().jjtGetParent().jjtGetNumChildren() > 1) {
// array element access
return true;
}
continue;
} else {
return true;
}
}
return false;
}
private boolean hasOverrideAnnotation(ASTMethodDeclaration node) {
int childIndex = node.jjtGetChildIndex();
for (int i = 0; i < childIndex; i++) {
Node previousSibling = node.jjtGetParent().jjtGetChild(i);
List<ASTMarkerAnnotation> annotations = previousSibling.findDescendantsOfType(ASTMarkerAnnotation.class);
for (ASTMarkerAnnotation annotation : annotations) {
ASTName name = annotation.getFirstChildOfType(ASTName.class);
if (name != null && (name.hasImageEqualTo("Override") || name.hasImageEqualTo("java.lang.Override"))) {
return true;
}
}
}
return false;
}
}