Notes on implementing google books api in java okhttp and gson versions and okhttp and jackson versions
It is a memo when I made a program application to register a book that I have on the web read with a barcode reader
okhttp and gson version
Overview
java
in maven
gson is a library for converting Java objects and JSON format data to each other.
gson version 2.8.6 used Site with explanation https://qiita.com/naoi/items/6b184700b2a41fb46356
OkHttp is an efficient HTTP client by default
Use okhttp version 3.7.0 Explanation site https://square.github.io/okhttp/
<dependency>
<groupId>com.google.code.gson</groupId>
<artifactId>gson</artifactId>
<version>2.8.6</version>
</dependency>
<dependency>
<groupId>com.squareup.okhttp3</groupId>
<artifactId>okhttp</artifactId>
<version>3.7.0</version>
</dependency>
google books api Official page https://developers.google.com/books/
This time, the code read by isbn with the barcode reader is sent as a request, so the code below is used.
https://www.googleapis.com/books/v1/volumes?q=isbn:Isbn code at the back
//It looks like below
https://www.googleapis.com/books/v1/volumes?q=isbn:9784844336778
json returned after sending a request with google books api
I'm not sure to be honest If there is a way to understand the hierarchy, please post it
// 20200101165936
// https://www.googleapis.com/books/v1/volumes?q=isbn:9784844336778
{
"kind": "books#volumes",
"totalItems": 1,
"items": [
{
"kind": "books#volume",
"id": "FQKOBAAAQBAJ",
"etag": "YZLyBEypyf4",
"selfLink": "https://www.googleapis.com/books/v1/volumes/FQKOBAAAQBAJ",
"volumeInfo": {
"title": "A refreshing introduction to Java Practical Edition 2nd Edition",
"authors": [
"Kiyotaka Nakayama"
],
"publisher": "Impress Corporation",
"publishedDate": "2014-09-22",
"description": "A revised version of Java 8's featured features such as lambda expressions and date APIs has been expanded, and agile-related and design patterns have been thoroughly strengthened! As with the sister book "Introduction to Java", the explanation will proceed while answering "Why?" Firmly, so knowledge essential for mastering Java at work, such as regular expressions, collections, database linkage, refactoring, parallel processing, etc. However, it is refreshing, fun, and easy to learn. Recommended for those who have understood the basic grammar and object-oriented concepts and want to take it even further. Issue",
"industryIdentifiers": [
{
"type": "ISBN_13",
"identifier": "9784844336778"
},
{
"type": "ISBN_10",
"identifier": "4844336770"
}
],
"readingModes": {
"text": false,
"image": true
},
"pageCount": 628,
"printType": "BOOK",
"categories": [
"Computers"
],
"maturityRating": "NOT_MATURE",
"allowAnonLogging": true,
"contentVersion": "2.3.0.0.preview.1",
"panelizationSummary": {
"containsEpubBubbles": false,
"containsImageBubbles": false
},
"imageLinks": {
"smallThumbnail": "http://books.google.com/books/content?id=FQKOBAAAQBAJ&printsec=frontcover&img=1&zoom=5&edge=curl&source=gbs_api",
"thumbnail": "http://books.google.com/books/content?id=FQKOBAAAQBAJ&printsec=frontcover&img=1&zoom=1&edge=curl&source=gbs_api"
},
"language": "ja",
"previewLink": "http://books.google.co.jp/books?id=FQKOBAAAQBAJ&printsec=frontcover&dq=isbn:9784844336778&hl=&cd=1&source=gbs_api",
"infoLink": "https://play.google.com/store/books/details?id=FQKOBAAAQBAJ&source=gbs_api",
"canonicalVolumeLink": "https://play.google.com/store/books/details?id=FQKOBAAAQBAJ"
},
"saleInfo": {
"country": "JP",
"saleability": "FOR_SALE",
"isEbook": true,
"listPrice": {
"amount": 2596.0,
"currencyCode": "JPY"
},
"retailPrice": {
"amount": 2336.0,
"currencyCode": "JPY"
},
"buyLink": "https://play.google.com/store/books/details?id=FQKOBAAAQBAJ&rdid=book-FQKOBAAAQBAJ&rdot=1&source=gbs_api",
"offers": [
{
"finskyOfferType": 1,
"listPrice": {
"amountInMicros": 2596000000,
"currencyCode": "JPY"
},
"retailPrice": {
"amountInMicros": 2336000000,
"currencyCode": "JPY"
}
}
]
},
"accessInfo": {
"country": "JP",
"viewability": "PARTIAL",
"embeddable": true,
"publicDomain": false,
"textToSpeechPermission": "ALLOWED",
"epub": {
"isAvailable": false
},
"pdf": {
"isAvailable": true,
"acsTokenLink": "http://books.google.co.jp/books/download/%E3%82%B9%E3%83%83%E3%82%AD%E3%83%AA%E3%82%8F%E3%81%8B%E3%82%8BJava%E5%85%A5%E9%96%80_%E5%AE%9F%E8%B7%B5-sample-pdf.acsm?id=FQKOBAAAQBAJ&format=pdf&output=acs4_fulfillment_token&dl_type=sample&source=gbs_api"
},
"webReaderLink": "http://play.google.com/books/reader?id=FQKOBAAAQBAJ&hl=&printsec=frontcover&source=gbs_api",
"accessViewStatus": "SAMPLE",
"quoteSharingAllowed": false
},
"searchInfo": {
"textSnippet": "A revised version of Java 8's featured features such as lambda expressions and date APIs has been expanded, and agile-related and design patterns have been thoroughly strengthened! Like the sister book "Introduction to Java", "Why?"..."
}
}
]
}
Generate JSON model class (pojo)
https://qiita.com/riversun/items/cdd990e96c2bbf9cb043 On this page, I referred to Automatically generate model class (pojo) using jsonschema2pojo.
Generated class file
The contents of the Model class
@SerializeName ("name") @Expose public type name
Since items is "items": [], it will be List
Caution
The model class is automatically generated, but it may be insufficient, so please make the one that is not generated by yourself.
java main code
package main;
import java.io.IOException;
import java.util.List;
import com.example.qson.Item;
import com.example.qson.ListPrice;
import com.example.qson.Model;
import com.example.qson.SaleInfo;
import com.example.qson.VolumeInfo;
import com.google.gson.Gson;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
public class main {
public static final String url = "https://www.googleapis.com/books/v1/volumes?q=isbn:";
public static void main(String[] args) {
//isbn code
Long isbn = 9784844336778L;
//Hold json
String json = "";
OkHttpClient okHttpClient;
okHttpClient = new OkHttpClient();
Request.Builder builder = new Request.Builder();
//Insert the address to send the request with url
builder.url(url + isbn);
Request request = builder.build();
Response response = null;
try {
response = okHttpClient.newCall(request).execute();
//I have the json information returned from the web api as mentioned above on the json here
json = response.body().string();
} catch (IOException e) {
e.printStackTrace();
}
Gson gson = new Gson();
Model models = gson.fromJson(json, Model.class);
List<Item> items2 = models.items;
VolumeInfo volumeInfo = items2.get(0).volumeInfo;
ImageLinks imageLinks = volumeInfo.imageLinks;
SaleInfo saleInfo = items2.get(0).saleInfo;
ListPrice listPrice = saleInfo.listPrice;
//When title is written from model class
//items class is List<Item>Because it is a type.get()Attach
System.out.println(models.items.get(0).volumeInfo.title);//title
//When the model class is changed to the volumeinfo class and displayed
System.out.println("title: " + volumeInfo.title);//title
System.out.println("author: " + volumeInfo.authors);//author
System.out.println("Publication date: " + volumeInfo.publishedDate);//publishedDate
System.out.println("the publisher: " + volumeInfo.publisher);//publisher
System.out.println("List price:" + listPrice.amount);
System.out.println("Description:" + volumeInfo.description);//description
System.out.println("number of pages:" + volumeInfo.pageCount);//pageCount
System.out.println("Small thumbnail:" + imageLinks.smallThumbnail);//smallThumbnail
System.out.println("thumbnail:" + imageLinks.thumbnail);//thumbnail
}
}
Execution result
I was able to go to the feeling
okhttp and jackson versions
Overview
java
in maven
OkHttp is an efficient HTTP client by default
Use okhttp version 3.7.0 Explanation site https://square.github.io/okhttp/
jackson
jackson-core version: 2.10.0 jackson-annotations version: 2.10.0 jackson-databind version: 2.10.0
Is put in
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>2.10.0</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-annotations</artifactId>
<version>2.10.0</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.10.0</version>
</dependency>
<dependency>
<groupId>com.squareup.okhttp3</groupId>
<artifactId>okhttp</artifactId>
<version>3.7.0</version>
</dependency>
java main
import java.io.IOException;
import java.sql.Date;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
public class main {
public static final String url = "https://www.googleapis.com/books/v1/volumes?q=isbn:";
public static void main(String[] args) {
//TODO auto-generated method stub
Long isbn = 9784295007807L;
//Hold json
String json ="";
//Book title
String title = "";
//author
String author = "";
//Publication date
Date publishedDate = null;
String day = "";
//the publisher
String publisher = "";
//List price
Integer listPrice = null;
//Explanatory text
String description = "";
//number of pages
Integer pageCount = null;
//small thumbnail
String smallThumbnail ="";
//thumbnail
String thumbnail = "";
OkHttpClient okHttpClient;
okHttpClient = new OkHttpClient();
Request.Builder builder = new Request.Builder();
//Insert the address to send the request with url
builder.url(url + isbn);
Request request = builder.build();
Response response = null;
try {
response = okHttpClient.newCall(request).execute();
json = response.body().string();
} catch (IOException e) {
e.printStackTrace();
}
//Display the contents of json
System.out.println(json);
//Processing to take out the contents of json from here and display it
ObjectMapper mapper = new ObjectMapper();
try {
JsonNode node = mapper.readTree(json);
//get("value")Value is json"title": "A refreshing introduction to Java Practical Edition 2nd Edition"
//The title part will be the value
//Since title is a String type, at the end.asText();Attach
title = node.get("items").get(0).get("volumeInfo").get("title").asText();
author = node.get("items").get(0).get("volumeInfo").get("authors").get(0).asText();
publisher = node.get("items").get(0).get("volumeInfo").get("publisher").asText();
//Received as String day to convert publication date to Date type
day = node.get("items").get(0).get("volumeInfo").get("publishedDate").textValue();
//Convert string to sql type Date
publishedDate = Date.valueOf(day);
//listPrice is an int type, so at the end.asInt();Attach
listPrice = node.get("items").get(0).get("saleInfo").get("listPrice").get("amount").asInt();
description = node.get("items").get(0).get("volumeInfo").get("description").asText();
pageCount = node.get("items").get(0).get("volumeInfo").get("pageCount").asInt();
smallThumbnail = node.get("items").get(0).get("volumeInfo").get("imageLinks").get("smallThumbnail").asText();
thumbnail = node.get("items").get(0).get("volumeInfo").get("imageLinks").get("thumbnail").asText();
} catch (IOException e) {
e.printStackTrace();
}
System.out.println("title: " +title);
System.out.println("author: " +author);
System.out.println("the publisher: "+publisher);
System.out.println("Publication date: " + publishedDate);
System.out.println("List price: " + listPrice + "Circle");
System.out.println("Explanatory text: " + description);
System.out.println("number of pages: " + pageCount);
System.out.println("Small thumbnail: " + smallThumbnail);
System.out.println("thumbnail: " +thumbnail);
}
}
I was able to do it like that
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