Collection to array

1. Object[]

   1	Object[] listArray = list.toArray();

2. specific array

   1	String[] listArray = (String[]) list.toArray(new String[0])

ps. it’s can’t be used to translate generic paradigm typed array

Array to collection

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List list = new ArrayList();
list = Arrays.asList(array);

ps. primary type can’t do it like this, it’s parameter must be objects

Use GZIPOutputStream ZipOutputStream packing the output
maybe it’s destination a file or a socket, it’s not the point. usually we use generic paradigm the reprecent the data source in stream and the compressed data out stream

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public static void compress(InputStream is, OutputStream os)
              throws Exception {

    GZIPOutputStream gos = new GZIPOutputStream(os);

    int count;
    byte data[] = new byte[BUFFER];
    while ((count = is.read(data, 0, BUFFER)) != -1) {
        gos.write(data, 0, count);
    }

    gos.finish();
    gos.flush();
    gos.close();
}

• RFC 3986 section 2.2 reserved january 2005

  1	! * '( ) ; : @& = + $ ,/ ? # [ ]

• RFC 3986 section 2.3 unreserved january 2005

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  A B C D E F G H I J K L M N O P Q RS T U V W X Y Z a b c d e f g h i j k l m n o p q rs t u v w x y z 0 1 2 3 4 5 6 7 8 9 - _ .~

• RFC 2396 URI Generic Syntax reserved August 1998

  1	; / ? : @ & = + $ ,

• RFC 2396 URI Generic Syntax unreserved August 1998

  1 2	alphanum or mark mark = - _ . ! ~ * ' ( )

java use the older one
for compatible java use the same collection unreserved from all browser just like RFC2986 no ‘~’ add ‘*’

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/*
 * Unreserved characters can be escaped without changing the
 * semantics of the URI, but this should not be done unless the
 * URI is being used in a context that does not allow the
 * unescaped character to appear.
 */

regular expression

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/^((ht|f)tps?):\/\/[\w\-]+(\.[\w\-]+)+([\w\-\.,@?^=%&:\/~\+#]*[\w\-\@?^=%&\/~\+#])?$/

• start with ‘http/https/ftp/ftps’
• can’t contain double bytes characters or not unreserved characters

Parameter ‘__frch_item_0’ not found. Available parameters are [list]

Mybatis parameter in list

1. 查看parameterType的类型是不是Java.util.List类型，如果是的话，看foreach 的collection属性是不是list，因为 传递一个 List 实例或者数组作为参数对象传给 MyBatis,MyBatis 会自动将它包装在一个 Map 中,用名称在作为键。List 实例将会以“list” 作为键,而数组实例将会以“array”作为键
   Is parameterType type Java.util.List. If it is, be caution foreach's collection must 'list'. Becase if put a List example or array to Mybatis, it will auto put it to a Map, use it's name as key, example as value. So Mybatis will put a special map to foreach
2. foreach is any value in list?
3. foreach is property spell error?
4. Mybatis set field auto increase but Mysql not.
5. Item’s property is not right

ps: use Map reduce Bean’s work, but question is if query result is null, then it’s corresponding property will lost(null)

Install & theme

use cnpm
npm install -g cnpm —registry=https://registry.npm.taobao.org

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sudo cnpm install hexo-cli -g
hexo init blog
cd blog

cnpm install
hexo server

# may ship
git clone https://github.com/tufu9441/maupassant-hexo.git themes/maupassant
npm install hexo-renderer-jade --save
npm install hexo-renderer-sass --save

npm install hexo-tag-katex --save

Optimization

• enter themes\landscape\layout_partial，open head.ejs，delete 31th row fonts.googleapis.com

• download jquery-2.0.3.min.js put into themes\landscape\source\js , enter themes\landscape\layout_partial, openafter-footer.ejs, replace 17th row to /js/jquery-2.0.3.min.js。

select count(*) from users WHERE id in ( ? , ? )

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<select id="countByUserList" resultType="_int" parameterType="list">    
select count(*) from users    
  <where>    
    id in    
    <foreach item="item" collection="list" separator="," open="(" close=")" index="">    
      #{item.id, jdbcType=NUMERIC}    
    </foreach>    
  </where>    
</select>

insert into deliver select ?,? from dual union all select ?,? from dual

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<insert id="addList">  
    INSERT INTO DELIVER  
        (  
            <include refid="selectAllColumnsSql"/>  
         )  

      <foreach collection="deliverList" item="item" separator="UNION ALL">  
            SELECT   
                 #{item.id, jdbcType=NUMERIC},  
                 #{item.name, jdbcType=VARCHAR}  
            FROM DUAL  
      </foreach>  
</insert>

insert into string_string (key, value) values (?, ?) , (?, ?)

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<insert id="ins_string_string">    
    insert into string_string (key, value) values    
    <foreach item="item" index="key" collection="map"    
        open="" separator="," close="">(#{key}, #{item})</foreach>    
</insert>

select count(*) from key_cols where col_a = ? AND col_b = ?

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<select id="sel_key_cols" resultType="int">    
    select count(*) from key_cols where    
    <foreach item="item" index="key" collection="map"    
        open="" separator="AND" close="">${key} = #{item}</foreach>    
</select>

ps: 一定要注意到$和#的区别，$的参数直接输出，#的参数会被替换为?，然后传入参数值执行。

No translate source dirctory

set _config.yml skip_render to ignore translate like:

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skip_render: Demo/*.html

or more complicated, base on regular expression(not strict)

1. under single dirctory all files:

   1	skip_render: demo/*

2. under single dirctory a type file:

   1	skip_render: demo/*.html

3. under single dirctory all files and children dirctory:

   1	skip_render: demo/**

4. complicated condition:

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   skip_render: - 'demo/*.html' - 'demo/**'

hello hexo

Command

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$ hexo init [folder]
$ hexo new [layout] <title>
$ hexo generate

config

  Website in subdirectory

If your website is in a subdirectory (such as http://example.org/blog) set url to http://example.org/blog and set root to /blog/
Ctrl+Alt+N

• hexo install
• hexo server
• hexo deploy

1. hexo install
2. hexo server
3. hexo deploy

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public staic void main(String[] args)

GitHub