[Fb-contrib-commit] SF.net SVN: fb-contrib:[1545] trunk/fb-contrib

[<dbr...@us...>]

Revision: 1545
          http://fb-contrib.svn.sourceforge.net/fb-contrib/?rev=1545&view=rev
Author:   dbrosius
Date:     2010-05-07 08:30:28 +0000 (Fri, 07 May 2010)

Log Message:
-----------
initial checkin, new WOC detector

Modified Paths:
--------------
    trunk/fb-contrib/etc/findbugs.xml
    trunk/fb-contrib/etc/messages.xml

Added Paths:
-----------
    trunk/fb-contrib/samples/WOC_Sample.java
    trunk/fb-contrib/src/com/mebigfatguy/fbcontrib/detect/WriteOnlyCollection.java

Modified: trunk/fb-contrib/etc/findbugs.xml
===================================================================
--- trunk/fb-contrib/etc/findbugs.xml	2010-04-24 01:53:11 UTC (rev 1544)
+++ trunk/fb-contrib/etc/findbugs.xml	2010-05-07 08:30:28 UTC (rev 1545)
@@ -331,6 +331,10 @@
 	<Detector class="com.mebigfatguy.fbcontrib.detect.PossibleConstantAllocationInLoop" 
 		speed="fast"
 		reports="PCAIL_POSSIBLE_CONSTANT_ALLOCATION_IN_LOOP" />
+		
+	<Detector class="com.mebigfatguy.fbcontrib.detect.WriteOnlyCollection"
+		speed="fast"
+		reports="WOC_WRITE_ONLY_COLLECTION" />
 				
 	<!-- BugPattern -->
 
@@ -627,4 +631,6 @@
 		category="CORRECTNESS" experimental="true" />
 	<BugPattern abbrev="PCAIL" type="PCAIL_POSSIBLE_CONSTANT_ALLOCATION_IN_LOOP"
 		category="PERFORMANCE" experimental="true" />
+	<BugPattern abbrev="WOC" type="WOC_WRITE_ONLY_COLLECTION"
+		category="CORRECTNESS" experimental="true" />
 </FindbugsPlugin>
\ No newline at end of file

Modified: trunk/fb-contrib/etc/messages.xml
===================================================================
--- trunk/fb-contrib/etc/messages.xml	2010-04-24 01:53:11 UTC (rev 1544)
+++ trunk/fb-contrib/etc/messages.xml	2010-05-07 08:30:28 UTC (rev 1545)
@@ -1134,6 +1134,17 @@
 	 		]]>
 	 	</Details>
 	 </Detector>
+	 
+	 <Detector class="com.mebigfatguy.fbcontrib.detect.WriteOnlyCollection">
+	 	<Details>
+	 		<![CDATA[
+	 		<p>This detector looks for allocations and initializations of java collections, but that are never
+	 		read from or accessed to gain information. This represents a collection of no use, and most probably
+	 		can be removed. It is similar to a dead local store.</p>
+	 		<p>It is a fast detector</p>
+	 		]]>
+	 	</Details>
+	 </Detector>
 
 	<!-- BugPattern -->	
 	                
@@ -3107,6 +3118,18 @@
 			]]>
 		</Details>
 	</BugPattern>
+	
+	<BugPattern type="WOC_WRITE_ONLY_COLLECTION">
+		<ShortDescription>Method creates and initializes a collection but never reads or gains information from it</ShortDescription>
+		<LongDescription>Method {1} creates and initializes a collection but never reads or gains information from it</LongDescription>
+		<Details>
+			<![CDATA[
+				<p>This method creates and initializes a collection but then never access this collection
+				to gain information, or fetch items from the collection. It is likely that this collection
+				is left over from a past effort, and can be removed.
+			]]>
+		</Details>
+	</BugPattern>
 
 	<!-- BugCode -->
 	
@@ -3203,4 +3226,5 @@
     	<BugCode abbrev="ROOM">Reflection on Object Methods</BugCode>
     	<BugCode abbrev="IPU">Improper Properties use</BugCode>
     	<BugCode abbrev="PCAIL">Possible Constant Allocation In Loop</BugCode>
+    	<BugCode abbrev="WOC">Write Only Collection</BugCode>
 </MessageCollection>

Added: trunk/fb-contrib/samples/WOC_Sample.java
===================================================================
--- trunk/fb-contrib/samples/WOC_Sample.java	                        (rev 0)
+++ trunk/fb-contrib/samples/WOC_Sample.java	2010-05-07 08:30:28 UTC (rev 1545)
@@ -0,0 +1,40 @@
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.LinkedHashSet;
+import java.util.Map;
+import java.util.Set;
+
+
+public class WOC_Sample 
+{
+	public void testWOCSimple()
+	{
+		Set<String> s = new HashSet<String>();
+		s.add("Foo");	
+	}
+	
+	public Map<String, String> testFPWOCReturn()
+	{
+		Map<String, String> m = new HashMap<String, String>();
+		m.put("Foo", "Bar");
+		return m;
+	}
+	
+	public void testFPWOCAsParm()
+	{
+		Map<String, String> m = new HashMap<String, String>();
+		m.put("Foo", "Bar");
+		helper(0, m);
+	}
+	
+	public void testFPWOCCopy()
+	{
+		Set<String> s = new LinkedHashSet<String>();
+		s.add("foo");
+		Set<String> c = s;
+	}
+	
+	private void helper(int i, Map<String, String> x)
+	{	
+	}
+}


Property changes on: trunk/fb-contrib/samples/WOC_Sample.java
___________________________________________________________________
Added: svn:mime-type
   + text/plain
Added: svn:eol-style
   + native

Added: trunk/fb-contrib/src/com/mebigfatguy/fbcontrib/detect/WriteOnlyCollection.java
===================================================================
--- trunk/fb-contrib/src/com/mebigfatguy/fbcontrib/detect/WriteOnlyCollection.java	                        (rev 0)
+++ trunk/fb-contrib/src/com/mebigfatguy/fbcontrib/detect/WriteOnlyCollection.java	2010-05-07 08:30:28 UTC (rev 1545)
@@ -0,0 +1,288 @@
+/*
+ * fb-contrib - Auxiliary detectors for Java programs
+ * Copyright (C) 2005-2010 Dave Brosius
+ * 
+ * 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 com.mebigfatguy.fbcontrib.detect;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Hashtable;
+import java.util.LinkedHashMap;
+import java.util.LinkedHashSet;
+import java.util.LinkedList;
+import java.util.Map;
+import java.util.Set;
+import java.util.TreeMap;
+import java.util.TreeSet;
+import java.util.Vector;
+
+import org.apache.bcel.Constants;
+import org.apache.bcel.classfile.Code;
+import org.apache.bcel.generic.Type;
+
+import com.mebigfatguy.fbcontrib.utils.RegisterUtils;
+
+import edu.umd.cs.findbugs.BugInstance;
+import edu.umd.cs.findbugs.BugReporter;
+import edu.umd.cs.findbugs.BytecodeScanningDetector;
+import edu.umd.cs.findbugs.OpcodeStack;
+import edu.umd.cs.findbugs.OpcodeStack.Item;
+import edu.umd.cs.findbugs.ba.ClassContext;
+import edu.umd.cs.findbugs.ba.XField;
+
+public class WriteOnlyCollection extends BytecodeScanningDetector {
+
+	private static Set<String> collectionClasses = new HashSet<String>();
+	static
+	{
+		collectionClasses.add(HashSet.class.getName());
+		collectionClasses.add(TreeSet.class.getName());
+		collectionClasses.add(LinkedHashSet.class.getName());		
+		collectionClasses.add(HashMap.class.getName());
+		collectionClasses.add(TreeMap.class.getName());
+		collectionClasses.add(Hashtable.class.getName());
+		collectionClasses.add(LinkedHashMap.class.getName());		
+		collectionClasses.add(Vector.class.getName());
+		collectionClasses.add(ArrayList.class.getName());
+		collectionClasses.add(LinkedList.class.getName());
+	}
+	
+	private static Set<String> writeMethods = new HashSet<String>();
+	static
+	{
+		writeMethods.add("add");
+		writeMethods.add("addAll");
+		writeMethods.add("addElement");
+		writeMethods.add("addFirst");
+		writeMethods.add("addLast");
+		writeMethods.add("clear");
+		writeMethods.add("clone");
+		writeMethods.add("ensureCapacity");
+		writeMethods.add("insertElementAt");
+		writeMethods.add("put");
+		writeMethods.add("putAll");
+		writeMethods.add("remove");
+		writeMethods.add("removeAll");
+		writeMethods.add("removeElement");
+		writeMethods.add("removeElementAt");
+		writeMethods.add("removeRange");
+		writeMethods.add("set");
+		writeMethods.add("setElementAt");
+		writeMethods.add("setSize");
+		writeMethods.add("trimToSize");
+	}
+	
+	private BugReporter bugReporter;
+	private OpcodeStack stack;
+	/** register to first allocation PC */
+	private Map<Integer, Integer> localWOCollections;
+	/** field to first allocation PC */
+	private Map<String, Integer> fieldWOCollections;
+	
+	
+	/**
+     * constructs a WOC detector given the reporter to report bugs on
+     * @param bugReporter the sync of bug reports
+	 */
+	public WriteOnlyCollection(BugReporter bugReporter) {
+		this.bugReporter = bugReporter;
+	}
+	/**
+	 * overrides the visitor to initialize and tear down the opcode stack
+	 * 
+	 * @param classContext the context object of the currently parsed class
+	 */
+	@Override
+	public void visitClassContext(ClassContext classContext) {
+		try {
+			stack = new OpcodeStack();
+			localWOCollections = new HashMap<Integer, Integer>();
+			fieldWOCollections = new HashMap<String, Integer>();
+			super.visitClassContext(classContext);
+		} finally {
+			stack = null;
+			localWOCollections = null;
+			fieldWOCollections = null;
+		}
+	}
+	
+	/**
+	 * overrides the visitor reset the stack
+	 * 
+	 * @param obj the context object of the currently parsed code block
+	 */
+	@Override
+	public void visitCode(Code obj) {
+		stack.resetForMethodEntry(this);
+		localWOCollections.clear();
+		super.visitCode(obj);
+		
+		for (Integer pc : localWOCollections.values()) {
+			bugReporter.reportBug(new BugInstance(this, "WOC_WRITE_ONLY_COLLECTION", NORMAL_PRIORITY)
+						.addClass(this)
+						.addMethod(this)
+						.addSourceLine(this, pc.intValue()));
+		}
+	}
+	
+	/**
+	 * overrides the visitor to look for uses of collections where the only access to
+	 * to the collection is to write to it
+	 * 
+	 * @param seen the opcode of the currently visited instruction
+	 */
+	@Override
+	public void sawOpcode(int seen) {
+		Object userObject = null;
+		
+		try {
+			switch (seen) {
+				case INVOKESPECIAL:
+					String methodName = getNameConstantOperand();
+					if ("<init>".equals(methodName)) {
+						String clsName = getClassConstantOperand().replace('/', '.');
+						if (collectionClasses.contains(clsName))
+							userObject = Boolean.TRUE;
+					}
+					processMethodParms();
+				break;
+				
+				case INVOKEINTERFACE:
+				case INVOKEVIRTUAL:
+					String sig = getSigConstantOperand();
+					int numParms = Type.getArgumentTypes(sig).length;
+					if (stack.getStackDepth() > numParms) {
+						OpcodeStack.Item item = stack.getStackItem(numParms);
+						Object uo = item.getUserValue();
+						if (uo != null) {
+							String name = getNameConstantOperand();
+							if (!writeMethods.contains(name)) {
+								clearUserValue(item);
+							}
+						}
+					}
+					processMethodParms();
+				break;
+				
+				case INVOKESTATIC:
+					processMethodParms();
+				break;
+				
+				case ARETURN:
+					if (stack.getStackDepth() > 0) {
+						OpcodeStack.Item item = stack.getStackItem(0);
+						clearUserValue(item);
+					}
+				break;
+				
+				case ASTORE_0:
+				case ASTORE_1:
+				case ASTORE_2:
+				case ASTORE_3:
+				case ASTORE:
+					if (stack.getStackDepth() > 0) {
+						OpcodeStack.Item item = stack.getStackItem(0);
+						Object uo = item.getUserValue();
+						if (uo != null) {
+							if (uo instanceof Boolean) {
+								int reg = RegisterUtils.getAStoreReg(this, seen);
+								localWOCollections.put(reg, Integer.valueOf(getPC()));
+							} else {
+								clearUserValue(item);
+							}
+						}
+					}
+				break;
+				
+				case ALOAD_0:
+				case ALOAD_1:
+				case ALOAD_2:
+				case ALOAD_3:
+				case ALOAD:
+					int reg = RegisterUtils.getALoadReg(this, seen);
+					if (localWOCollections.containsKey(Integer.valueOf(reg))) {
+						userObject = Integer.valueOf(reg);
+					}
+				break;
+				
+				case PUTFIELD:
+					if (stack.getStackDepth() > 1) {
+						OpcodeStack.Item item = stack.getStackItem(0);
+						Object uo = item.getUserValue();
+						if (uo != null) {
+							if (uo instanceof Boolean) {
+								Item fieldItem = stack.getStackItem(1);
+								boolean storedInThis = fieldItem.getRegisterNumber() == 0;
+								if (storedInThis) {	
+									XField field = getXFieldOperand();
+									if ((field.getAccessFlags() & Constants.ACC_PRIVATE) != 0) {
+										String fieldName = field.getName();
+										fieldWOCollections.put(fieldName, getPC());
+									}
+								}
+							} else {
+								clearUserValue(item);
+							}
+						}
+					}
+				break;
+				
+				case GETFIELD:
+					if (stack.getStackDepth() > 0) {
+						OpcodeStack.Item item = stack.getStackItem(0);
+						if (item.getRegisterNumber() == 0) {
+							XField field = getXFieldOperand();
+							String fieldName = field.getName();
+							if (fieldWOCollections.containsKey(fieldName)) {
+								userObject = fieldName;
+							}
+						}
+					}
+				break;
+			}
+		} finally {
+			stack.sawOpcode(this, seen);
+			if (userObject != null) {
+				if (stack.getStackDepth() > 0) {
+					OpcodeStack.Item item = stack.getStackItem(0);
+					item.setUserValue(userObject);
+				}
+			}
+		}
+	}
+	
+	private void clearUserValue(OpcodeStack.Item item) {
+		Object uo = item.getUserValue();
+		if (uo instanceof Integer) {
+			localWOCollections.remove(uo);
+		} else if (uo instanceof String) {
+			fieldWOCollections.remove(uo);
+		}
+		item.setUserValue(null);
+	}
+	
+	private void processMethodParms() {
+		String sig = getSigConstantOperand();
+		int numParms = Type.getArgumentTypes(sig).length;
+		if (stack.getStackDepth() >= numParms) {
+			for (int i = 0; i < numParms; i++) {
+				clearUserValue(stack.getStackItem(i));
+			}
+		}
+	}
+}


Property changes on: trunk/fb-contrib/src/com/mebigfatguy/fbcontrib/detect/WriteOnlyCollection.java
___________________________________________________________________
Added: svn:mime-type
   + text/plain
Added: svn:eol-style
   + native


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