2 files changed, 146 insertions, 0 deletions
diff --git a/docs/examples/tracing/version1/Trace.java b/docs/examples/tracing/version1/Trace.java
new file mode 100644
index 000000000..97b5edb3f
--- /dev/null
+++ b/docs/examples/tracing/version1/Trace.java
@@ -0,0 +1,77 @@
+/*
+Copyright (c) Xerox Corporation 1998-2002.  All rights reserved.
+
+Use and copying of this software and preparation of derivative works based
+upon this software are permitted.  Any distribution of this software or
+derivative works must comply with all applicable United States export control
+laws.
+
+This software is made available AS IS, and Xerox Corporation makes no warranty
+about the software, its performance or its conformity to any specification.
+*/
+
+package tracing.version1;
+
+import java.io.PrintStream;
+
+/**
+ *
+ * This class provides some basic functionality for printing trace messages
+ * into a stream.
+ *
+ */
+public class Trace {
+    /**
+     * There are 3 trace levels (values of TRACELEVEL):
+     * 0 - No messages are printed
+     * 1 - Trace messages are printed, but there is no indentation
+     *     according to the call stack
+     * 2 - Trace messages are printed, and they are indented
+     *     according to the call stack
+     */
+    public static int TRACELEVEL = 0;
+    protected static PrintStream stream = null;
+    protected static int callDepth = 0;
+
+    /**
+     * Initialization.
+     */
+    public static void initStream(PrintStream s) {
+        stream = s;
+    }
+
+    /**
+     * Prints an "entering" message. It is intended to be called in the
+     * beginning of the blocks to be traced.
+     */
+    public static void traceEntry(String str) {
+        if (TRACELEVEL == 0) return;
+        if (TRACELEVEL == 2) callDepth++;
+        printEntering(str);
+    }
+
+    /**
+     * Prints an "exiting" message. It is intended to be called in the
+     * end of the blocks to be traced.
+     */
+    public static void traceExit(String str) {
+        if (TRACELEVEL == 0) return;
+        printExiting(str);
+        if (TRACELEVEL == 2) callDepth--;
+    }
+
+    private static void printEntering(String str) {
+        printIndent();
+        stream.println("--> " + str);
+    }
+
+    private static void printExiting(String str) {
+        printIndent();
+        stream.println("<-- " + str);
+    }
+
+    private static void printIndent() {
+        for (int i = 0; i < callDepth; i++)
+            stream.print("  ");
+    }
+}
diff --git a/docs/examples/tracing/version1/TraceMyClasses.java b/docs/examples/tracing/version1/TraceMyClasses.java
new file mode 100644
index 000000000..736e96413
--- /dev/null
+++ b/docs/examples/tracing/version1/TraceMyClasses.java
@@ -0,0 +1,69 @@
+/*
+Copyright (c) Xerox Corporation 1998-2002.  All rights reserved.
+
+Use and copying of this software and preparation of derivative works based
+upon this software are permitted.  Any distribution of this software or
+derivative works must comply with all applicable United States export control
+laws.
+
+This software is made available AS IS, and Xerox Corporation makes no warranty
+about the software, its performance or its conformity to any specification.
+*/
+
+package tracing.version1;
+
+/**
+ *
+ * This class connects the tracing functions in the Trace class with
+ * the constructors and methods in the application classes.
+ *
+ */
+import tracing.TwoDShape;
+import tracing.Circle;
+import tracing.Square;
+import tracing.ExampleMain;
+
+aspect TraceMyClasses {
+    /**
+     * Application classes.
+     */
+    pointcut myClass(): within(TwoDShape) || within(Circle) || within(Square);
+    /**
+     * The constructors in those classes.
+     */
+    pointcut myConstructor(): myClass() && execution(new(..));
+    /**
+     * The methods of those classes.
+     */
+    pointcut myMethod(): myClass() && execution(* *(..));
+
+    /**
+     * Prints trace messages before and after executing constructors.
+     */
+    before (): myConstructor() {
+        Trace.traceEntry("" + thisJoinPointStaticPart.getSignature());
+    }
+    after(): myConstructor() {
+        Trace.traceExit("" + thisJoinPointStaticPart.getSignature());
+    }
+
+    /**
+     * Prints trace messages before and after executing methods.
+     */
+    before (): myMethod() {
+        Trace.traceEntry("" + thisJoinPointStaticPart.getSignature());
+    }
+    after(): myMethod() {
+        Trace.traceExit("" + thisJoinPointStaticPart.getSignature());
+    }
+
+    /**
+     * A main function for testing the trace aspect.
+     */
+    public static void main(String[] args) {
+        Trace.TRACELEVEL = 2;
+        Trace.initStream(System.err);
+        ExampleMain.main(args);
+    }
+}
+