书接上文：JsonPath 实践（一）
本期聊一下如何使用JSonpath标记语法处理，json对象中的数组主要内容是提取数组中对象和对象集合。
首先看官方给的json数据的Demo（我做了一点点修改）：
JSONObject json = JSON.parseObject("{" +
" \"store\": {" +
" \"book\": [" +
" {" +
" \"category\": \"reference\"," +
" \"author\": \"Nigel Rees\"," +
" \"title\": \"Sayings of the Century\"," +
" \"price\": 8.95" +
" }," +
" {" +
" \"category\": \"fiction\"," +
" \"author\": \"Evelyn Waugh\"," +
" \"title\": \"Sword of Honour\"," +
" \"price\": 12.99" +
" }," +
" {" +
" \"category\": \"fiction\"," +
" \"author\": \"Herman Melville\"," +
" \"title\": \"Moby Dick\"," +
" \"isbn\": \"0-553-21311-3\"," +
" \"price\": 8.99" +
" }," +
" {" +
" \"category\": \"fiction\"," +
" \"author\": \"J. R. R. Tolkien\"," +
" \"title\": \"The Lord of the Rings\"," +
" \"isbn\": \"0-395-19395-8\"," +
" \"price\": 22.99" +
" }" +
" ]," +
" \"bicycle\": {" +
" \"color\": \"red\"," +
" \"price\": 19.95" +
" }" +
" }," +
" \"expensive\": 10," +
" \"ss\": [32,32,4,23]" +
"}");
jsonpath：$.store.book[2]
jsonpath：$.store.book[-1]
代码：
Object read = JsonPath.read(json, "$.store.book[2]");
output(JSON.parseObject(read.toString()));
等效写法：
JSONObject read = JsonPath.read(json, "$.store.book[2]");
output(read);
控制台输出：
INFO-> 当前用户：fv，IP：10.60.131.54，工作目录：/Users/fv/Documents/workspace/fun/,系统编码格式:UTF-8,系统Mac OS X版本:10.15.6
INFO->
~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~ JSON ~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~
＞ {
＞ ① . "author":"Herman Melville",
＞ ① . "price":8.99,
＞ ① . "isbn":"0-553-21311-3",
＞ ① . "category":"fiction",
＞ ① . "title":"Moby Dick"
＞ }
~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~ JSON ~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~
Process finished with exit code 0
Python中对于数组的处理。jsonpath：$.store.book[:2]
jsonpath：$.store.book[-2:]
代码：
Object read = JsonPath.read(json, "$.store.book[2]");
output(JSON.parseObject(read.toString()));
等效写法省略……
控制台输出：
INFO-> 当前用户：fv，IP：10.60.192.21，工作目录：/Users/fv/Documents/workspace/fun/,系统编码格式:UTF-8,系统Mac OS X版本:10.15.6
INFO->
~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~ JSON ~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~
＞ {
＞ ① . "author":"Nigel Rees",
＞ ① . "price":8.95,
＞ ① . "category":"reference",
＞ ① . "title":"Sayings of the Century"
＞ }
~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~ JSON ~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~
INFO->
~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~ JSON ~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~
＞ {
＞ ① . "author":"Evelyn Waugh",
＞ ① . "price":12.99,
＞ ① . "category":"fiction",
＞ ① . "title":"Sword of Honour"
＞ }
~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~ JSON ~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~
Process finished with exit code 0
INFO-> 当前用户：fv，IP：10.60.192.21，工作目录：/Users/fv/Documents/workspace/fun/,系统编码格式:UTF-8,系统Mac OS X版本:10.15.6
INFO->
~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~ JSON ~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~
＞ {
＞ ① . "author":"Herman Melville",
＞ ① . "price":8.99,
＞ ① . "isbn":"0-553-21311-3",
＞ ① . "category":"fiction",
＞ ① . "title":"Moby Dick"
＞ }
~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~ JSON ~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~
INFO->
~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~ JSON ~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~
＞ {
＞ ① . "author":"J. R. R. Tolkien",
＞ ① . "price":22.99,
＞ ① . "isbn":"0-395-19395-8",
＞ ① . "category":"fiction",
＞ ① . "title":"The Lord of the Rings"
＞ }
~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~ JSON ~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~~☢~
Process finished with exit code 0