Debug.java

package net.sourceforge.solexatools; // -*- tab-width: 4 -*-

import javax.servlet.http.HttpServletRequest;
import net.sourceforge.seqware.common.util.Log;

/**
 * <p>
 * Debug class.
 * </p>
 * 
 * @author boconnor
 * @version $Id: $Id
 */
public class Debug {
    // Produces: "((ImplementingClassName)InstanceClassName)"
    // or: "ClassName"
    // ... in the case where the implementing class and class of the instance differ
    // or are the same respectively.
    /**
     * <p>
     * describeInterfaceAndImplementation.
     * </p>
     * 
     * @param instance
     *            a {@link java.lang.Object} object.
     * @param implClassName
     *            a {@link java.lang.String} object.
     * @return a {@link java.lang.String} object.
     */
    public static String describeInterfaceAndImplementation(Object instance, String implClassName) {
        String instanceClassName = (instance != null ? instance.getClass().getName() : "");
        boolean implAlsoDefinesInterfaceP = instanceClassName.equals(implClassName);
        int afterLastDot;

        afterLastDot = instanceClassName.lastIndexOf('.') + 1;
        if (afterLastDot < 0) {
            afterLastDot = 0;
        }
        instanceClassName = instanceClassName.substring(afterLastDot);

        afterLastDot = implClassName.lastIndexOf('.') + 1;
        if (afterLastDot < 0) {
            afterLastDot = 0;
        }
        implClassName = implClassName.substring(afterLastDot);

        if (implAlsoDefinesInterfaceP) return implClassName;

        return "((" + implClassName + ")" + instanceClassName + ")";
    }

    /**
     * <p>
     * put.
     * </p>
     * 
     * @param request
     *            a {@link javax.servlet.http.HttpServletRequest} object.
     */
    public static void put(HttpServletRequest request) {
        putImpl(null,
                "" + "{ request.getPathInfo() = " + request.getPathInfo() + ", request.getPathTranslated() = "
                        + request.getPathTranslated() + ", request.getRequestURI() = " + request.getRequestURI()
                        + ", request.getServletPath() = " + request.getServletPath() + "}");
    }

    /**
     * <p>
     * put.
     * </p>
     * 
     * @param message
     *            a {@link java.lang.String} object.
     */
    public static void put(String message) {
        putImpl(null, message);
    }

    /**
     * <p>
     * put.
     * </p>
     * 
     * @param instance
     *            a {@link java.lang.Object} object.
     * @param message
     *            a {@link java.lang.String} object.
     */
    public static void put(Object instance, String message) {
        putImpl(instance, message);
    }

    // It is important that both interfaces above call this implementation
    // directly and not each other because of the levels of stack that
    // are ignored in the expression:
    // StackTraceElement caller = stack[4];
    // ... below.
    private static void putImpl(Object instance, String message) {
        // return; /* // Uncoment this line at the beginning with '//' in order to enable debug messages
        Thread current = Thread.currentThread();
        StackTraceElement[] stack = current.getStackTrace();
        StackTraceElement caller = stack[4];

        // //////////////////////////////////////////////////////////////////////
        // build indentation to indicate call-depth
        String indent = "";
        for (int i = stack.length - 1; i > 0; i--) {
            String implClassName = stack[i].getClassName();
            if (!implClassName.startsWith("net.sourceforge.solexatools")) continue;

            // having more padding near "base" of stack is more important:
            // -for(int j = (int)(Math.log(i)/Math.log(2.0)); j > 0; j--) {
            indent += "    ";
            // -}
        }

        // //////////////////////////////////////////////////////////////////////
        // build final message
        String msg = "T" + current.getId() + ": " + caller.getFileName() + ":" // maybe null
                + caller.getLineNumber() + ":" // maybe negative
        ;

        while (msg.length() < 50)
            msg += " "; // pad to fixed width

        msg += "" + indent + describeInterfaceAndImplementation(instance, caller.getClassName()) + "." + caller.getMethodName() + message;

        // show it
        Log.info(msg); // */
    }
}

// ex:sw=4:ts=4: