Use isEmpty() in preference to size()

java/Makefile

@@ -758,9 +758,12 @@ very_clean: very-clean
 very-clean: clean clean-generated-files
 	-rm -f TAGS
 	-rm -rf dcomp_premain.jar dcomp_rt.jar ${DCOMP_RT}
-	-rm -rf api
-	-rm -rf daikon/dcomp/std_dcomp_out.diff daikon/dcomp/std_dcomp_out.txt
+	-rm -rf api/
 	-rm -rf daikon/chicory/ChicoryTest.inv.out
+	-rm -rf daikon/chicory/debug/
+	-rm -rf daikon/dcomp/debug/
+	-rm -rf daikon/dcomp/DcompTest.log
+	-rm -rf daikon/dcomp/std_dcomp_out.diff daikon/dcomp/std_dcomp_out.txt
 
 run:	all
 	${JAVA_COMMAND} daikon.Daikon

java/daikon/AnnotateNullable.java

@@ -169,9 +169,15 @@ public static void main(String[] args) throws IOException {
     }
   }
 
-  // Returns null if no corresponding class ppt exists
+  /**
+   * Returns the class program point corresponding to an object program point. Returns null if no
+   * corresponding class ppt exists.
+   *
+   * @param object_ppt an object program point
+   * @return the class program point corresponding to an object program point
+   */
   private static @Nullable PptTopLevel class_for_object(PptTopLevel object_ppt) {
-    if (object_ppt.parents.size() == 0) {
+    if (object_ppt.parents.isEmpty()) {
       return null;
     }
     assert object_ppt.parents.size() == 1 : object_ppt;

java/daikon/Daikon.java

@@ -740,7 +740,7 @@ public static void mainHelper(final String[] args) {
     Set<String> dtrace_files = files.dtrace;
     Set<File> spinfo_files = files.spinfo;
     Set<File> map_files = files.map;
-    if (server_dir == null && (decls_files.size() == 0) && (dtrace_files.size() == 0)) {
+    if (server_dir == null && decls_files.isEmpty() && dtrace_files.isEmpty()) {
       System.out.println("No .decls or .dtrace files specified");
       throw new Daikon.UserError("No .decls or .dtrace files specified");
     }
@@ -1813,7 +1813,7 @@ public static void createUpperPpts(PptMap all_ppts) {
     for (PptTopLevel ppt : all_ppts.pptIterable()) {
       // System.out.printf("considering ppt %s parents: %s, children: %s%n",
       //                     ppt.name, ppt.parents, ppt.children);
-      if (ppt.parents.size() == 0) {
+      if (ppt.parents.isEmpty()) {
         ppt.mergeInvs();
       }
     }
@@ -2082,7 +2082,7 @@ private static PptMap load_decls_files(Set<File> decl_files) {
         debugTrace.fine("Initializing partial order");
       }
       fileio_progress.clear();
-      if (!Daikon.dkconfig_quiet && decl_files.size() > 0) {
+      if (!Daikon.dkconfig_quiet && !decl_files.isEmpty()) {
         System.out.print("\r(read ");
         System.out.print(StringsPlume.nplural(decl_files.size(), "decls file"));
         System.out.println(")");
@@ -2131,7 +2131,7 @@ private static void load_spinfo_files(Set<File> spinfo_files) {
    */
   private static void load_map_files(Set<File> map_files) {
     long startTime = System.nanoTime();
-    if (!PptSplitter.dkconfig_disable_splitting && map_files.size() > 0) {
+    if (!PptSplitter.dkconfig_disable_splitting && !map_files.isEmpty()) {
       System.out.print("Reading map (context) files ");
       ContextSplitterFactory.load_mapfiles_into_splitterlist(
           map_files, ContextSplitterFactory.dkconfig_granularity);
@@ -2360,7 +2360,7 @@ private static void process_data(PptMap all_ppts, Set<String> dtrace_files) {
           String.format("Finished reading %d samples", FileIO.samples_processed));
     }
 
-    if (all_ppts.size() == 0) {
+    if (all_ppts.isEmpty()) {
       String message = "No program point declarations were found.";
       if (FileIO.omitted_declarations != 0) {
         message +=
@@ -2765,7 +2765,7 @@ public static void undoOpts(PptMap all_ppts) {
           }
         }
 
-        if (vars.size() > 0) {
+        if (!vars.isEmpty()) {
 
           // Create new equality sets for all of the non-equal vars
           List<Equality> newInvs = sliceEquality.createEqualityInvs(vars, eq);

java/daikon/DaikonSimple.java

@@ -108,7 +108,7 @@ public static void mainHelper(final String[] args) throws IOException, FileNotFo
     Set<File> decls_files = files.decls;
     Set<String> dtrace_files = files.dtrace;
 
-    if ((decls_files.size() == 0) && (dtrace_files.size() == 0)) {
+    if (decls_files.isEmpty() && dtrace_files.isEmpty()) {
       throw new Daikon.UserError("No .decls or .dtrace files specified");
     }
 
@@ -594,7 +594,7 @@ private void add(PptTopLevel ppt, ValueTuple vt, int nonce) {
         // DaikonSimple will not do this to be consistent.
         // The better idea is for Daikon to assert that these valuetuples are
         // empty and then skip the sample.
-        assert vt.size() == 0;
+        assert vt.isEmpty();
         return;
       }
 

java/daikon/Debug.java

@@ -193,7 +193,7 @@ public Debug(Class<?> c, Ppt ppt, List<VarInfo> vis) {
     VarInfo v = visTracked(vis);
     if (v != null) {
       set(c, ppt, new VarInfo[] {v});
-    } else if (vis.size() > 0) {
+    } else if (!vis.isEmpty()) {
       set(c, ppt, new VarInfo[] {vis.get(0)});
     } else {
       set(c, ppt, null);

java/daikon/DynamicConstants.java

@@ -517,7 +517,7 @@ public void instantiate_new_views(List<Constant> noncons, List<Constant> non_mis
     // the remaining constants and the newly-non constants.  Any slices
     // between the non-constants and other variables will have already
     // been created when those other variables became non-constants.
-    if (noncons.size() > 0) {
+    if (!noncons.isEmpty()) {
       List<Constant> cons = new ArrayList<>();
       cons.addAll(con_list);
       cons.addAll(noncons);
@@ -528,7 +528,7 @@ public void instantiate_new_views(List<Constant> noncons, List<Constant> non_mis
     // Create all views over the newly non-missing.  Since missing
     // vars were not included in any previous views, we must match them
     // against all variables.
-    if (non_missing.size() > 0) {
+    if (!non_missing.isEmpty()) {
       debug.fine("Instantiating non missing in ppt: " + ppt.name());
       instantiate_views(non_missing, all_list);
     }
@@ -699,7 +699,7 @@ private void instantiate_views(List<Constant> list1, List<Constant> list2) {
             inv.log("Invariant %s destroyed by constant values %s", inv.format(), vals);
           }
         }
-        if (slice.invs.size() > 0) {
+        if (!slice.invs.isEmpty()) {
           slice_cnt[slice.arity()]++;
         }
         inv_cnt[slice.arity()] += slice.invs.size();
@@ -1096,7 +1096,7 @@ public List<PptSlice> create_constant_invs() {
         assert con.val != null : "@AssumeAssertion(nullness): dependent: val when count>0";
         slice1.add_val_bu(con.val, mod, con.count);
       }
-      if (slice1.invs.size() > 0) {
+      if (!slice1.invs.isEmpty()) {
         new_views.add(slice1);
       }
     }
@@ -1124,7 +1124,7 @@ public List<PptSlice> create_constant_invs() {
               : "@AssumeAssertion(nullness): dependent: val != null when count>0";
           slice2.add_val_bu(con1.val, con2.val, mod, mod, con1.count);
         }
-        if (slice2.invs.size() > 0) {
+        if (!slice2.invs.isEmpty()) {
           new_views.add(slice2);
         }
       }

java/daikon/FileIO.java

@@ -1753,7 +1753,7 @@ public static void read_data_trace_record(ParseState state) throws IOException {
         throw new Daikon.UserError(message, reader, state.filename);
       }
 
-      if (state.all_ppts.size() == 0) {
+      if (state.all_ppts.isEmpty()) {
         throw new Daikon.UserError(
             "No declarations were provided before the first sample.  Perhaps you did not supply"
                 + " the proper .decls file to Daikon.  (Or, there could be a bug in the front end"

java/daikon/MergeInvariants.java

@@ -225,7 +225,7 @@ public static void mainHelper(String[] args)
 
     // if no decls file was specified
     if (decl_file == null) {
-      if (splitter_files.size() > 0) {
+      if (!splitter_files.isEmpty()) {
         throw new Daikon.UserError(".spinfo files may only be specified along with a .decls file");
       }
 
@@ -288,11 +288,11 @@ public static void mainHelper(String[] args)
 
       // Skip everything that is not a final exit point
       if (!ppt.ppt_name.isExitPoint()) {
-        assert ppt.children.size() > 0 : ppt;
+        assert !ppt.children.isEmpty() : ppt;
         continue;
       }
       if (ppt.ppt_name.isCombinedExitPoint()) {
-        assert ppt.children.size() > 0 : ppt;
+        assert !ppt.children.isEmpty() : ppt;
         continue;
       }
 
@@ -304,7 +304,7 @@ public static void mainHelper(String[] args)
         assert ppt.splitters != null; // because ppt.has_splitters() = true
         for (PptSplitter ppt_split : ppt.splitters) {
           for (PptTopLevel p : ppt_split.ppts) {
-            assert p.children.size() == 0 : p;
+            assert p.children.isEmpty() : p;
           }
         }
       }
@@ -356,12 +356,12 @@ public static void mainHelper(String[] args)
       }
 
       // Make sure at least one child was found
-      assert ppt.children.size() > 0 : ppt;
+      assert !ppt.children.isEmpty() : ppt;
       if (ppt.has_splitters()) {
         assert ppt.splitters != null; // because ppt.has_splitters() = true
         for (PptSplitter ppt_split : ppt.splitters) {
           for (PptTopLevel p : ppt_split.ppts) {
-            assert p.children.size() > 0 : p;
+            assert !p.children.isEmpty() : p;
           }
         }
       }
@@ -374,7 +374,7 @@ public static void mainHelper(String[] args)
     if (debug.isLoggable(FINE)) {
       debug.fine("PPT Hierarchy");
       for (PptTopLevel ppt : merge_ppts.pptIterable()) {
-        if (ppt.parents.size() == 0) {
+        if (ppt.parents.isEmpty()) {
           ppt.debug_print_tree(debug, 0, null);
         }
       }

java/daikon/PptMap.java

@@ -246,6 +246,16 @@ public int size() {
     return nameToPpt.size();
   }
 
+  /**
+   * Returns true if this PptMap is empty.
+   *
+   * @return true if this PptMap is empty
+   */
+  @Pure
+  public boolean isEmpty() {
+    return size() == 0;
+  }
+
   @SideEffectFree
   @Override
   public String toString(@GuardSatisfied PptMap this) {

java/daikon/PptRelation.java

@@ -114,6 +114,16 @@ public int size() {
     return parent_to_child_map.size();
   }
 
+  /**
+   * Returns true if this PptRelation is empty.
+   *
+   * @return true if this PptRelation is empty
+   */
+  @Pure
+  public boolean isEmpty() {
+    return parent_to_child_map.isEmpty();
+  }
+
   @SideEffectFree
   @Override
   public String toString(@GuardSatisfied PptRelation this) {
@@ -215,7 +225,7 @@ public PptRelationType getRelationType() {
 
   /** Returns true if this relation's child has children of its own. */
   public boolean hasChildren() {
-    return (child.children.size() > 0);
+    return !child.children.isEmpty();
   }
 
   /**
@@ -859,7 +869,7 @@ public static void init_hierarchy(PptMap all_ppts) {
     if (debug.isLoggable(Level.FINE)) {
       debug.fine("PPT Hierarchy");
       for (PptTopLevel ppt : all_ppts.pptIterable()) {
-        if (ppt.parents.size() == 0) {
+        if (ppt.parents.isEmpty()) {
           ppt.debug_print_tree(debug, 0, null);
         }
       }
@@ -1019,7 +1029,7 @@ public static void init_hierarchy_new(PptMap all_ppts) {
     // happen when there are ppts such as OBJECT or CLASS that don't end up
     // with any children (due to the program source or because of ppt filtering).
     for (PptTopLevel ppt : all_ppts.pptIterable()) {
-      if ((ppt.children.size() == 0) && (ppt.equality_view == null)) {
+      if (ppt.children.isEmpty() && (ppt.equality_view == null)) {
         assert ppt.is_object() || ppt.is_class() || ppt.is_enter() : ppt;
         ppt.equality_view = new PptSliceEquality(ppt);
         ppt.equality_view.instantiate_invariants();
@@ -1030,7 +1040,7 @@ public static void init_hierarchy_new(PptMap all_ppts) {
     if (debug.isLoggable(Level.FINE)) {
       debug.fine("PPT Hierarchy");
       for (PptTopLevel ppt : all_ppts.pptIterable()) {
-        if (ppt.parents.size() == 0) {
+        if (ppt.parents.isEmpty()) {
           ppt.debug_print_tree(debug, 0, null);
         }
       }

java/daikon/PptSlice.java

@@ -143,7 +143,7 @@ public void removeInvariant(Invariant inv) {
     boolean removed = invs.remove(inv);
     assert removed : "inv " + inv + " not in ppt " + name();
     Global.falsified_invariants++;
-    if (invs.size() == 0) {
+    if (invs.isEmpty()) {
       if (Debug.logDetail()) {
         log("last invariant removed");
       }
@@ -163,7 +163,7 @@ public void removeInvariants(List<Invariant> to_remove) {
       invs.removeAll(to_remove);
       assert old_invs_size - invs.size() == to_remove.size();
       Global.falsified_invariants += to_remove.size();
-      if (invs.size() == 0) {
+      if (invs.isEmpty()) {
         if (Debug.logDetail()) {
           log("last invariant removed");
         }
@@ -267,7 +267,7 @@ public boolean containsOnlyGuardingPredicates() {
 
   /** Remove the invariants noted in omitTypes. */
   public void processOmissions(boolean[] omitTypes) {
-    if (invs.size() == 0) {
+    if (invs.isEmpty()) {
       return;
     }
     List<Invariant> toRemove = new ArrayList<>();