文件过滤 看 java 回调

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运行，输出结果为
类型的文件: a.txt
类型的文件: b.txt
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查看源码：
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/**     * Returns an array of strings naming the files and directories in the     * directory denoted by this abstract pathname that satisfy the specified     * filter.  The behavior of this method is the same as that of the     * <code>{@link #list()}</code> method, except that the strings in the     * returned array must satisfy the filter.  If the given     * <code>filter</code> is <code>null</code> then all names are accepted.     * Otherwise, a name satisfies the filter if and only if the value     * <code>true</code> results when the <code>{@link     * FilenameFilter#accept}</code> method of the filter is invoked on this     * abstract pathname and the name of a file or directory in the directory     * that it denotes.     *     * @param  filter  A filename filter     *     * @return  An array of strings naming the files and directories in the     *          directory denoted by this abstract pathname that were accepted     *          by the given <code>filter</code>.  The array will be empty if     *          the directory is empty or if no names were accepted by the     *          filter.  Returns <code>null</code> if this abstract pathname     *          does not denote a directory, or if an I/O error occurs.     *     * @throws  SecurityException     *          If a security manager exists and its <code>{@link     *          java.lang.SecurityManager#checkRead(java.lang.String)}</code>     *          method denies read access to the directory     */    public String[] list(FilenameFilter filter) {String names[] = list();if ((names == null) || (filter == null)) {    return names;}ArrayList v = new ArrayList();for (int i = 0 ; i < names.length ; i++) {    if (filter.accept(this, names[i])) {v.add(names[i]);    }}return (String[])(v.toArray(new String[0]));    }
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很优雅.......
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使用内部类 更优雅
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http://www.blogjava.net/hwpok/archive/2008/04/01/190196.html
http://blog.sina.com.cn/s/blog_48cf38890100go6x.html
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