上述方法几乎没有问题
1jsonloader总是期望输入的完整模式，但您只给出了三个字段。
2jsonloader总是希望整个输入都是一行，但是您的输入是多行的。
三。jsonloader不支持嵌套模式，但您的输入包含嵌套模式。
要解决以上所有问题，您必须使用第三方库 elephant-bird jar .
从这个链接下载（elephant-bird-pig-4.1.jar和elephant-bird-hadoop-compat-4.1.jar）jar文件http://www.java2s.com/code/jar/e/elephant.htm 尝试下面的方法
我复制了您的全部输入，并格式化为一行，如下所示。
输入.json

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://t.co/DDco9wVXtP","geo":null,"retweeted":false,"in_reply_to_screen_name":"MinaANDMaya","possibly_sensitive":false,"truncated":false,"lang":"en","entities":{"trends":[],"symbols":[],"urls":[{"expanded_url":"https://www.animalfriendsquote.co.uk/fb-worldcup/","indices":[93,116],"display_url":"animalfriendsquote.co.uk/fb-worldcup/","url":"https://t.co/Y8g47fLYY1"}],"hashtags":[],"media":[{"sizes":{"thumb":{"w":150,"resize":"crop","h":150},"small":{"w":340,"resize":"fit","h":455},"large":{"w":706,"resize":"fit","h":946},"medium":{"w":600,"resize":"fit","h":803}},"id":488926730481332224,"media_url_https":"https://pbs.twimg.com/media/BskERVuIcAAJZGu.jpg","media_url":"http://pbs.twimg.com/media/BskERVuIcAAJZGu.jpg","expanded_url":"http://twitter.com/BulleyBufton/status/488926827394904064/photo/1","indices":[117,139],"id_str":"488926730481332224","type":"photo","display_url":"pic.twitter.com/DDco9wVXtP","url":"http://t.co/DDco9wVXtP"}],"user_mentions":[{"id":132204038,"name":"Mina*Bad Yoga 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2014","default_profile_image":false,"followers_count":311,"profile_image_url_https":"https://pbs.twimg.com/profile_images/478106512083017728/4ao_8JjE_normal.jpeg","geo_enabled":false,"profile_background_image_url":"http://pbs.twimg.com/profile_background_images/431815421189029888/YrRNpUfd.jpeg","profile_background_image_url_https":"https://pbs.twimg.com/profile_background_images/431815421189029888/YrRNpUfd.jpeg","follow_request_sent":null,"url":null,"utc_offset":null,"time_zone":null,"notifications":null,"profile_use_background_image":true,"friends_count":455,"profile_sidebar_fill_color":"DDEEF6","screen_name":"winnie341881","id_str":"2272804116","profile_image_url":"http://pbs.twimg.com/profile_images/478106512083017728/4ao_8JjE_normal.jpeg","listed_count":0,"is_translator":false}}

Pig手稿：

REGISTER '/tmp/elephant-bird-hadoop-compat-4.1.jar';
REGISTER '/tmp/elephant-bird-pig-4.1.jar';

A = LOAD 'input.json ' USING com.twitter.elephantbird.pig.load.JsonLoader('-nestedLoad') AS myMap;
B = FOREACH A GENERATE myMap#'id' AS ID,myMap#'created_at' AS createdAT,myMap#'user' AS User;
DUMP B;

输出：

(488927960280211456,Tue Jul 15 06:08:04 +0000 2014,[location#,default_profile#false,profile_background_tile#true,statuses_count#1370,lang#zh-tw,profile_link_color#038544,profile_banner_url#https://pbs.twimg.com/profile_banners/2272804116/1404662156,id#2272804116,following#,protected#false,favourites_count#2000,profile_text_color#333333,contributors_enabled#false,description#No More Sorrow,verified#false,name#Winnie,profile_sidebar_border_color#000000,profile_background_color#14DBBA,created_at#Thu Jan 02 10:13:01 +0000 2014,default_profile_image#false,followers_count#311,geo_enabled#false,profile_image_url_https#https://pbs.twimg.com/profile_images/478106512083017728/4ao_8JjE_normal.jpeg,profile_background_image_url#http://pbs.twimg.com/profile_background_images/431815421189029888/YrRNpUfd.jpeg,profile_background_image_url_https#https://pbs.twimg.com/profile_background_images/431815421189029888/YrRNpUfd.jpeg,follow_request_sent#,url#,utc_offset#,time_zone#,notifications#,friends_count#455,profile_use_background_image#true,profile_sidebar_fill_color#DDEEF6,screen_name#winnie341881,id_str#2272804116,profile_image_url#http://pbs.twimg.com/profile_images/478106512083017728/4ao_8JjE_normal.jpeg,is_translator#false,listed_count#0])

在 elephantbird library 所有的值都是 stored as key/value pair(ie MAP datatype) ，因此可以很容易地从加载的数据中提取所需的字段。
在上面的pigscript中，我提取了 'id','created_at' and 'user' 根据你的需要。假设您想从'user'数据中提取一些字段（ ex: 'friends_count' and 'followers_count' )，在这种情况下，您需要投影 'user' 字段并提取所需的数据。下面是示例代码。
Pig手稿：

REGISTER '/tmp/elephant-bird-hadoop-compat-4.1.jar';
REGISTER '/tmp/elephant-bird-pig-4.1.jar';

A = LOAD 'input.json ' USING com.twitter.elephantbird.pig.load.JsonLoader('-nestedLoad') AS myMap;
B = FOREACH A GENERATE 'user' AS User;
C = FOREACH B GENERATE User#'friends_count', User#'followers_count';
DUMP C;

输出：

(455,311)