introspectionutils.java

业界著名的tomcat服务器的最新6.0的源代码。

                if ("setProperty".equals(methods[i].getName())) {
                    setPropertyMethod = methods[i];
                }
            }

            // Ok, no setXXX found, try a setProperty("name", "value")
            if (setPropertyMethod != null) {
                Object params[] = new Object[2];
                params[0] = name;
                params[1] = value;
                setPropertyMethod.invoke(o, params);
            }

        } catch (IllegalArgumentException ex2) {
            log.warn("IAE " + o + " " + name + " " + value, ex2);
        } catch (SecurityException ex1) {
            if (dbg > 0)
                d("SecurityException for " + o.getClass() + " " + name + "="
                        + value + ")");
            if (dbg > 1)
                ex1.printStackTrace();
        } catch (IllegalAccessException iae) {
            if (dbg > 0)
                d("IllegalAccessException for " + o.getClass() + " " + name
                        + "=" + value + ")");
            if (dbg > 1)
                iae.printStackTrace();
        } catch (InvocationTargetException ie) {
            if (dbg > 0)
                d("InvocationTargetException for " + o.getClass() + " " + name
                        + "=" + value + ")");
            if (dbg > 1)
                ie.printStackTrace();
        }
    }

    public static Object getProperty(Object o, String name) {
        String getter = "get" + capitalize(name);
        String isGetter = "is" + capitalize(name);

        try {
            Method methods[] = findMethods(o.getClass());
            Method getPropertyMethod = null;

            // First, the ideal case - a getFoo() method
            for (int i = 0; i < methods.length; i++) {
                Class paramT[] = methods[i].getParameterTypes();
                if (getter.equals(methods[i].getName()) && paramT.length == 0) {
                    return methods[i].invoke(o, (Object[]) null);
                }
                if (isGetter.equals(methods[i].getName()) && paramT.length == 0) {
                    return methods[i].invoke(o, (Object[]) null);
                }

                if ("getProperty".equals(methods[i].getName())) {
                    getPropertyMethod = methods[i];
                }
            }

            // Ok, no setXXX found, try a getProperty("name")
            if (getPropertyMethod != null) {
                Object params[] = new Object[1];
                params[0] = name;
                return getPropertyMethod.invoke(o, params);
            }

        } catch (IllegalArgumentException ex2) {
            log.warn("IAE " + o + " " + name, ex2);
        } catch (SecurityException ex1) {
            if (dbg > 0)
                d("SecurityException for " + o.getClass() + " " + name + ")");
            if (dbg > 1)
                ex1.printStackTrace();
        } catch (IllegalAccessException iae) {
            if (dbg > 0)
                d("IllegalAccessException for " + o.getClass() + " " + name
                        + ")");
            if (dbg > 1)
                iae.printStackTrace();
        } catch (InvocationTargetException ie) {
            if (dbg > 0)
                d("InvocationTargetException for " + o.getClass() + " " + name
                        + ")");
            if (dbg > 1)
                ie.printStackTrace();
        }
        return null;
    }

    /**
     */
    public static void setProperty(Object o, String name) {
        String setter = "set" + capitalize(name);
        try {
            Method methods[] = findMethods(o.getClass());
            Method setPropertyMethod = null;
            // find setFoo() method
            for (int i = 0; i < methods.length; i++) {
                Class paramT[] = methods[i].getParameterTypes();
                if (setter.equals(methods[i].getName()) && paramT.length == 0) {
                    methods[i].invoke(o, new Object[] {});
                    return;
                }
            }
        } catch (Exception ex1) {
            if (dbg > 0)
                d("Exception for " + o.getClass() + " " + name);
            if (dbg > 1)
                ex1.printStackTrace();
        }
    }

    /**
     * Replace ${NAME} with the property value
     *
     * @deprecated Use the explicit method
     */
    public static String replaceProperties(String value, Object getter) {
        if (getter instanceof Hashtable)
            return replaceProperties(value, (Hashtable) getter, null);

        if (getter instanceof PropertySource) {
            PropertySource src[] = new PropertySource[] { (PropertySource) getter };
            return replaceProperties(value, null, src);
        }
        return value;
    }

    /**
     * Replace ${NAME} with the property value
     */
    public static String replaceProperties(String value, Hashtable staticProp,
            PropertySource dynamicProp[]) {
        StringBuffer sb = new StringBuffer();
        int prev = 0;
        // assert value!=nil
        int pos;
        while ((pos = value.indexOf("$", prev)) >= 0) {
            if (pos > 0) {
                sb.append(value.substring(prev, pos));
            }
            if (pos == (value.length() - 1)) {
                sb.append('$');
                prev = pos + 1;
            } else if (value.charAt(pos + 1) != '{') {
                sb.append('$');
                prev = pos + 1; // XXX
            } else {
                int endName = value.indexOf('}', pos);
                if (endName < 0) {
                    sb.append(value.substring(pos));
                    prev = value.length();
                    continue;
                }
                String n = value.substring(pos + 2, endName);
                String v = null;
                if (staticProp != null) {
                    v = (String) ((Hashtable) staticProp).get(n);
                }
                if (v == null && dynamicProp != null) {
                    for (int i = 0; i < dynamicProp.length; i++) {
                        v = dynamicProp[i].getProperty(n);
                        if (v != null) {
                            break;
                        }
                    }
                }
                if (v == null)
                    v = "${" + n + "}";

                sb.append(v);
                prev = endName + 1;
            }
        }
        if (prev < value.length())
            sb.append(value.substring(prev));
        return sb.toString();
    }

    /**
     * Reverse of Introspector.decapitalize
     */
    public static String capitalize(String name) {
        if (name == null || name.length() == 0) {
            return name;
        }
        char chars[] = name.toCharArray();
        chars[0] = Character.toUpperCase(chars[0]);
        return new String(chars);
    }

    public static String unCapitalize(String name) {
        if (name == null || name.length() == 0) {
            return name;
        }
        char chars[] = name.toCharArray();
        chars[0] = Character.toLowerCase(chars[0]);
        return new String(chars);
    }

    // -------------------- Class path tools --------------------

    /**
     * Add all the jar files in a dir to the classpath, represented as a Vector
     * of URLs.
     */
    public static void addToClassPath(Vector cpV, String dir) {
        try {
            String cpComp[] = getFilesByExt(dir, ".jar");
            if (cpComp != null) {
                int jarCount = cpComp.length;
                for (int i = 0; i < jarCount; i++) {
                    URL url = getURL(dir, cpComp[i]);
                    if (url != null)
                        cpV.addElement(url);
                }
            }
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }

    public static void addToolsJar(Vector v) {
        try {
            // Add tools.jar in any case
            File f = new File(System.getProperty("java.home")
                    + "/../lib/tools.jar");

            if (!f.exists()) {
                // On some systems java.home gets set to the root of jdk.
                // That's a bug, but we can work around and be nice.
                f = new File(System.getProperty("java.home") + "/lib/tools.jar");
                if (f.exists()) {
                    if (log.isDebugEnabled())
                        log.debug("Detected strange java.home value "
                            + System.getProperty("java.home")
                            + ", it should point to jre");
                }
            }
            URL url = new URL("file", "", f.getAbsolutePath());

            v.addElement(url);
        } catch (MalformedURLException ex) {
            ex.printStackTrace();
        }
    }

    /**
     * Return all files with a given extension in a dir
     */
    public static String[] getFilesByExt(String ld, String ext) {
        File dir = new File(ld);
        String[] names = null;
        final String lext = ext;
        if (dir.isDirectory()) {
            names = dir.list(new FilenameFilter() {
                public boolean accept(File d, String name) {
                    if (name.endsWith(lext)) {
                        return true;
                    }
                    return false;
                }
            });
        }
        return names;
    }

    /**
     * Construct a file url from a file, using a base dir
     */
    public static URL getURL(String base, String file) {
        try {
            File baseF = new File(base);
            File f = new File(baseF, file);
            String path = f.getCanonicalPath();
            if (f.isDirectory()) {
                path += "/";
            }
            if (!f.exists())
                return null;
            return new URL("file", "", path);
        } catch (Exception ex) {
            ex.printStackTrace();
            return null;
        }
    }

    /**
     * Add elements from the classpath <i>cp </i> to a Vector <i>jars </i> as
     * file URLs (We use Vector for JDK 1.1 compat).
     * <p>
     *
     * @param jars The jar list
     * @param cp a String classpath of directory or jar file elements
     *   separated by path.separator delimiters.
     * @throws IOException If an I/O error occurs
     * @throws MalformedURLException Doh ;)
     */
    public static void addJarsFromClassPath(Vector jars, String cp)
            throws IOException, MalformedURLException {
        String sep = System.getProperty("path.separator");
        String token;
        StringTokenizer st;
        if (cp != null) {
            st = new StringTokenizer(cp, sep);
            while (st.hasMoreTokens()) {
                File f = new File(st.nextToken());
                String path = f.getCanonicalPath();
                if (f.isDirectory()) {
                    path += "/";
                }
                URL url = new URL("file", "", path);
                if (!jars.contains(url)) {
                    jars.addElement(url);
                }
            }
        }
    }

    /**
     * Return a URL[] that can be used to construct a class loader
     */
    public static URL[] getClassPath(Vector v) {
        URL[] urls = new URL[v.size()];
        for (int i = 0; i < v.size(); i++) {
            urls[i] = (URL) v.elementAt(i);
        }
        return urls;
    }

    /**
     * Construct a URL classpath from files in a directory, a cpath property,
     * and tools.jar.
     */
    public static URL[] getClassPath(String dir, String cpath,