The Backyard - DumpObjectBug Diff

CodeZineに掲載したプログラムにバグがありました。

http://codezine.jp/a/article/aid/95.aspx

!!パッチ

diff -u DumpObject.java~ DumpObject.java
--- DumpObject.java~ Mon Jun 13 01:15:38 2005
+++ DumpObject.java Thu Nov 16 22:05:22 2006
@@ -29,6 +29,25 @@
      public DumpObject(Object o) {
          target = o;
      }
+
+    class EmbededKey {
+        Class cls;
+        Object obj;
+        EmbededKey(Class c, Object o) {
+            obj = o;
+            cls = c;
+        }
+        public boolean equals(Object o) {
+            if (o instanceof EmbededKey) {
+                return ((EmbededKey)o).cls == cls && ((EmbededKey)o).obj == obj;
+            }
+            return false;
+        }
+        public int hashCode() {
+            return cls.hashCode() ^ obj.hashCode();
+        }
+    }
+    
      /**
       * オブジェクトを文字列化する。
       * @return オブジェクトの文字列表現
@@ -63,8 +82,9 @@
              }
              buffer.append(']');
          } else {
-            if (embeded.containsKey(o)) {
-                 buffer.append('(').append(embeded.get(o)).append(')');
+            EmbededKey ekey = new EmbededKey(c, o);
+            if (embeded.containsKey(ekey)) {
+                buffer.append('(').append(embeded.get(ekey)).append(')');
              } else {
                  buffer.append(dumpObject(c, o, level));
              }
@@ -82,7 +102,7 @@
          } catch (NoSuchMethodException e) { // never
              return o.toString();
          }
-        embeded.put(o, o.toString());
+        embeded.put(new EmbededKey(c, o), o.toString());
          StringBuffer buffer = new StringBuffer();
          buffer.append(o.toString());
          buffer.append(dumpFields(c, o, level));

!!テストと結果
!!!継承クラス

    static class DerivedSimpleClass extends SimpleClass {
        private String strValue2 = "string2";
    }
    // 継承オブジェクト
    public void testDerivedSimpleClass() throws Exception {
        DerivedSimpleClass o = new DerivedSimpleClass();
        DumpObject dob = new DumpObject(o);
        assertEquals(o + LF + "strValue2=\"string2\"" + LF +
                     o + LF + "strValue=\"string\"" + LF +
                     "intValue=32" + LF + "b=[ 1, 2, 3, 4, 5, ]",
                     dob.toString());
    }

!!!インナークラス

    static class Outer {
        class Inner {
            private String inner = "inner";
        }
        Inner createInner() {
            return new Inner();
        }
        private String outer = "outer";
    }


    public void testInnerClass() throws Exception {
        Outer o = new Outer();
        Outer.Inner i = o.createInner();
        DumpObject dob = new DumpObject(i);
        // とりあえず表示してみる
        System.out.println(dob.toString());
    }

出力

com.example.tool.DumpObjectTest$Outer$Inner@6bade9
inner="inner"
this$1=com.example.tool.DumpObjectTest$Outer@b5dac4
   outer="outer"
   this$0=testInnerClass(com.example.tool.DumpObjectTest)