/*
 * FindBugs - Find bugs in Java programs
 * Copyright (C) 2005 Dave Brosius <dbrosius@users.sourceforge.net>
 * Copyright (C) 2005 University of Maryland
 * 
 * This library 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 2.1 of the License, or (at your option) any later version.
 * 
 * This library 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 library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package edu.umd.cs.findbugs.detect;

import org.apache.bcel.Repository;
import org.apache.bcel.classfile.JavaClass;

import edu.umd.cs.findbugs.BugInstance;
import edu.umd.cs.findbugs.BugReporter;
import edu.umd.cs.findbugs.Detector;
import edu.umd.cs.findbugs.StatelessDetector;
import edu.umd.cs.findbugs.ba.AnalysisContext;
import edu.umd.cs.findbugs.ba.ClassContext;
import edu.umd.cs.findbugs.visitclass.Constants2;
import edu.umd.cs.findbugs.visitclass.PreorderVisitor;

public class RedundantInterfaces extends PreorderVisitor implements Detector, Constants2, StatelessDetector
{
	private BugReporter bugReporter;
	
	public RedundantInterfaces(BugReporter bugReporter) {
		this.bugReporter = bugReporter;
	}
	
	public Object clone() throws CloneNotSupportedException {
		return super.clone();
	}
	
	public void visitClassContext(ClassContext classContext) {
		JavaClass obj = classContext.getJavaClass();

		String superClassName = obj.getSuperclassName();
		if (superClassName.equals("java.lang.Object"))
			return;
		
		String[] interfaceNames = obj.getInterfaceNames();
		if ((interfaceNames == null) || (interfaceNames.length == 0))
			return;

		try {
			JavaClass superObj = obj.getSuperClass();
			
			for (int i = 0; i < interfaceNames.length; i++) {
				JavaClass inf = Repository.lookupClass(interfaceNames[i]);
				if (superObj.instanceOf(inf)) {
					bugReporter.reportBug( new BugInstance( this, "RI_REDUNDANT_INTERFACES", LOW_PRIORITY )
						.addClass(obj)
						.addClass(inf));
				}
			}
		} catch (ClassNotFoundException cnfe) {
			bugReporter.reportMissingClass(cnfe);
		}
	}

	public void setAnalysisContext(AnalysisContext analysisContext) {
	}
	
	public void report() {
	}
}

/*
 * FindBugs - Find bugs in Java programs
 * Copyright (C) 2005 Dave Brosius <dbrosius@users.sourceforge.net>
 * Copyright (C) 2005 University of Maryland
 * 
 * This library 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 2.1 of the License, or (at your option) any later version.
 * 
 * This library 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 library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package edu.umd.cs.findbugs.detect;

import java.util.Iterator;
import java.util.SortedSet;
import java.util.TreeSet;

import org.apache.bcel.Repository;
import org.apache.bcel.classfile.JavaClass;

import edu.umd.cs.findbugs.BugInstance;
import edu.umd.cs.findbugs.BugReporter;
import edu.umd.cs.findbugs.Detector;
import edu.umd.cs.findbugs.StatelessDetector;
import edu.umd.cs.findbugs.ba.AnalysisContext;
import edu.umd.cs.findbugs.ba.ClassContext;
import edu.umd.cs.findbugs.visitclass.Constants2;
import edu.umd.cs.findbugs.visitclass.PreorderVisitor;

public class RedundantInterfaces extends PreorderVisitor implements Detector, Constants2, StatelessDetector
{
	private BugReporter bugReporter;
	
	public RedundantInterfaces(BugReporter bugReporter) {
		this.bugReporter = bugReporter;
	}
	
	public Object clone() throws CloneNotSupportedException {
		return super.clone();
	}
	
	public void visitClassContext(ClassContext classContext) {
		JavaClass obj = classContext.getJavaClass();

		String superClassName = obj.getSuperclassName();
		if (superClassName.equals("java.lang.Object"))
			return;
		
		String[] interfaceNames = obj.getInterfaceNames();
		if ((interfaceNames == null) || (interfaceNames.length == 0))
			return;

		try {
			JavaClass superObj = obj.getSuperClass();
			SortedSet<String> redundantInfNames = new TreeSet<String>();
			
			for (int i = 0; i < interfaceNames.length; i++) {
				JavaClass inf = Repository.lookupClass(interfaceNames[i]);
				if (superObj.instanceOf(inf))
					redundantInfNames.add(inf.getClassName());
			}
				
			if (redundantInfNames.size() > 0) {
				BugInstance bug = new BugInstance( this, "RI_REDUNDANT_INTERFACES", LOW_PRIORITY )
							.addClass(obj);
				Iterator<String> it = redundantInfNames.iterator();
				while (it.hasNext())
					bug.addClass(it.next());
					
				bugReporter.reportBug(bug);
			}

		} catch (ClassNotFoundException cnfe) {
			bugReporter.reportMissingClass(cnfe);
		}
	}

	public void setAnalysisContext(AnalysisContext analysisContext) {
	}
	
	public void report() {
	}
}

refactor so that each src class only produces at most one bug report, even if it implements multiple interfaces that super classes implement. All are listed in the one report.