boilerplate testing

X-SVN-Rev: 14567

icu4j/src/com/ibm/icu/dev/test/TestBoilerplate.java

@@ -0,0 +1,191 @@
+package com.ibm.icu.dev.test;
+
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Method;
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.TreeSet;
+
+import com.ibm.icu.text.UnicodeSet;
+
+/**
+ * To use, override the abstract and the protected methods as necessary.
+ * Tests boilerplate invariants:
+ * <br>a.equals(a)
+ * <br>!a.equals(null)
+ * <br>if a.equals(b) then 
+ * <br>(1) a.hashCode() == b.hashCode  // note: the reverse is not necessarily true.
+ * <br>(2) a functions in all aspects as equivalent to b
+ * <br>(3) b.equals(a)
+ * <br>if b = clone(a)
+ * <br>(1) b.equals(a), and the above checks
+ * <br>(2) if mutable(a), then a.clone() != a // note: the reverse is not necessarily true.
+ * @author Davis
+ */
+public abstract class TestBoilerplate extends TestFmwk {
+
+    public final void TestMain() throws Exception {
+        List list = new LinkedList();
+        while (_addTestObject(list));
+        Object[] testArray = list.toArray();
+        for (int i = 0; i < testArray.length; ++i) {
+            //logln("Testing " + i);
+            Object a = testArray[i];
+            int aHash = a.hashCode();
+            if (a.equals(null)) {
+                errln("Equality/Null invariant fails: " + i);
+            }
+            if (!a.equals(a)) {
+                errln("Self-Equality invariant fails: " + i);
+            }
+            Object b;                
+            if (_canClone(a)) {
+                b = _clone(a);
+                if (b == a) {
+                    if (_isMutable(a)) {
+                        errln("Clone/Mutability invariant fails: " + i);
+                    }
+                } else {
+                    if (!a.equals(b)) {
+                        errln("Clone/Equality invariant fails: " + i);
+                    }
+                }
+                _checkEquals(i, -1, a, aHash, b);
+            }
+            for (int j = i; j < testArray.length; ++j) {
+                b = testArray[j];
+                if (a.equals(b)) _checkEquals(i, j, a, aHash, b);
+            }
+        }
+    }
+
+    private void _checkEquals(int i, int j, Object a, int aHash, Object b) {
+        int bHash = b.hashCode();
+        if (!b.equals(a)) errln("Equality/Symmetry",i, j);
+        if (aHash != bHash) errln("Equality/Hash",i, j);
+        if (a != b && !_hasSameBehavior(a,b)) {
+            errln("Equality/Equivalence",i, j);
+        }
+    }
+
+    private void errln(String title, int i, int j) {
+        if (j < 0) errln("Clone/" + title + "invariant fails: " + i);
+        else errln(title + "invariant fails: " + i + "," + j);
+    }
+
+    /**
+     * Must be overridden to check whether a and be behave the same
+     * @param a
+     * @param b
+     * @return
+     */
+    protected abstract boolean _hasSameBehavior(Object a, Object b);
+
+    /**
+     * This method will be called multiple times until false is returned.
+     * The results should be a mixture of different objects of the same
+     * type: some equal and most not equal.
+     * The subclasser controls how many are produced (recommend about 
+     * 100, based on the size of the objects and how costly they are
+     * to run this test on. The running time grows with the square of the
+     * count.
+     * NOTE: this method will only be called if the objects test as equal.
+     * @return
+     */
+    protected abstract boolean _addTestObject(List c);
+    /**
+     * Override if the tested objects are mutable.
+     * <br>Since Java doesn't tell us, we need a function to tell if so.
+     * The default is true, so must be overridden if not.
+     * @return
+     */
+    protected boolean _isMutable(Object a) {
+        return true;
+    }
+    /**
+     * Override if the tested objects can be cloned.
+     * @return
+     */
+    protected boolean _canClone(Object a) {
+        return true;
+    }
+    /**
+     * Produce a clone of the object. Tries two methods
+     * (a) clone
+     * (b) constructor
+     * Must be overridden if _canClone returns true and
+     * the above methods don't work.
+     * @param a
+     * @return clone
+     */
+    protected Object _clone(Object a) throws Exception {
+        Class aClass = a.getClass();
+        try {
+            Method cloner = aClass.getMethod("clone", null);
+            return cloner.invoke(a,null);
+        } catch (NoSuchMethodException e) {
+            Constructor constructor = aClass.getConstructor(new Class[] {aClass});
+            return constructor.newInstance(new Object[]{a});
+        }
+    }
+    
+    /* Utilities */
+    public static boolean verifySetsIdentical(AbstractTestLog here, UnicodeSet set1, UnicodeSet set2) {
+        if (set1.equals(set2)) return true;
+        here.errln("Sets differ:");
+        here.errln("UnicodeMap - HashMap");
+        here.errln(new UnicodeSet(set1).removeAll(set2).toPattern(true));
+        here.errln("HashMap - UnicodeMap");
+        here.errln(new UnicodeSet(set2).removeAll(set1).toPattern(true));
+        return false;
+    }
+
+    public static boolean verifySetsIdentical(AbstractTestLog here, Set values1, Set values2) {
+        if (values1.equals(values2)) return true;
+        Set temp;
+        here.errln("Values differ:");
+        here.errln("UnicodeMap - HashMap");
+        temp = new TreeSet(values1);
+        temp.removeAll(values2);
+        here.errln(show(temp));
+        here.errln("HashMap - UnicodeMap");
+        temp = new TreeSet(values2);
+        temp.removeAll(values1);
+        here.errln(show(temp));
+        return false;
+    }
+    
+    public static String show(Map m) {
+        StringBuffer buffer = new StringBuffer();
+        for (Iterator it = m.keySet().iterator(); it.hasNext();) {
+            Object key = it.next();
+            buffer.append(key + "=>" + m.get(key) + "\r\n");
+        }
+        return buffer.toString();
+    }
+    
+    public static UnicodeSet getSet(Map m, Object value) {
+        UnicodeSet result = new UnicodeSet();
+        for (Iterator it = m.keySet().iterator(); it.hasNext();) {
+            Object key = it.next();
+            Object val = m.get(key);
+            if (!val.equals(value)) continue;
+            result.add(((Integer)key).intValue());
+        }
+        return result;
+    }
+    
+    public static String show(Collection c) {
+        StringBuffer buffer = new StringBuffer();
+        for (Iterator it = c.iterator(); it.hasNext();) {
+            buffer.append(it.next() + "\r\n");
+        }
+        return buffer.toString();
+    }
+    
+
+}