Java Web Service - java-json.jar包的使用以及JDBC的配置链接

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Preface

• 本Sample是对上一篇java web service 的延续，主要说明创建java web service项目的简要过程
• 网上很多关于JDBC的链接sample都会在src/下创建dto(Data Transaction Objects)、model、webService、pojo(Plain Old Java Object)等几个package分属不同功能，本sample为简洁起见，将功能都放入了webService中
• 本文原创，允许转载但务必贴出本文链接

环境&工具

• Jersey JAX-RS 2.0 RI bundle 解压后将所有.jar文件放在WebContent>WEB-INF>lib下面
• json.jar 注：因为eclipse有特殊的喜好，在web servicejar 工程中，jar包的引用根据web容器而有所不同，对于tomcat，所有引用.jar必须放在web-info/lib/下
• mysql-connector-java-5.1.35.tar.gz注：需要向oracle出卖自己的email他才会让你下这个东西，之和后json.jar一样需要放在web-info/lib/下
• java version “1.8.0_40”
• tomcat 8.0
• eclipse Luna
• mysql 5.6.19

建立简单的get、post web service以及一个客户端

• 该步骤请参考:
  一个包含Jersey库的简单Web Service以及一个发送Json数据的Java客户端

在mysql中创建database Library 并insert 一些数据

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create database Library;use Librarycreate table `Book` (    `id`    int(11) NOT NULL AUTO_INCREMENT,    `title` text    NOT NULL,    `description`   text    NULL,    PRIMARY KEY(`id`));insert into Book (title, description) values("Stardust", "Stardust is a novel by Neil Gaiman, usually published with illustrations by Charles Vess. Stardust has a different tone and style from most of Gaiman''s prose fiction, being consciously written in the tradition of pre-Tolkien English fantasy, following in the footsteps of authors such as Lord Dunsany and Hope Mirrlees. It is concerned with the adventures of a young man from the village of Wall, which borders the magical land of Faerie.");insert into Book (title) values("testTitle2"),("testTitle3");

修改你的RestService类

内容如下：

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package simpleRestWebService;import java.io.BufferedReader;import java.io.InputStream;import java.io.InputStreamReader;import javax.ws.rs.GET;import javax.ws.rs.Produces;import javax.ws.rs.Consumes;import javax.ws.rs.POST;import javax.ws.rs.Path;import javax.ws.rs.core.MediaType;import javax.ws.rs.core.Response;import org.json.JSONException;import org.json.JSONObject;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import com.mysql.jdbc.Connection;import com.mysql.jdbc.PreparedStatement;@Path("/restService")public class RestService {    @POST    @Consumes(MediaType.APPLICATION_JSON)    public Response json_restResponse(InputStream incomingData) {        // json receiving variables        String receivedString = "";        JSONObject receivedJson = null;        // configuration of data source connection         String driver = "com.mysql.jdbc.Driver";          String url = "jdbc:mysql://127.0.0.1:3306/Library";          String usr = "root";        String pwd = "123456";        // connection variables        PreparedStatement stmt = null;        Connection conn = null;        // temp variables        // returnCode will be send to client and be present in the console view        String returnCode = "SEARCH PROGRESS & RESULTS:";        // receive the json data as receivedJson(JSONObject)        try {            BufferedReader in = new BufferedReader(new InputStreamReader(incomingData));            String line = null;            while ((line = in.readLine()) != null) {                receivedString += line;            }            try {                receivedJson = new JSONObject(receivedString);                returnCode += "\n\n- receive json data successfully...";            }            catch (JSONException e){                System.out.println("Error new Json - ");            }        }        catch (Exception e) {            System.out.println("Error Parsing: - ");        }        // load JDBC driver        try {            Class.forName(driver).newInstance();            returnCode += "\n\n- the driver is on...";        }         catch(Exception e) {            e.printStackTrace();        }        // connect to mysql database "Library" and search for book with "title" = "Stardust"        try {            conn = (Connection) DriverManager.getConnection(url, usr, pwd);            stmt = (PreparedStatement) conn.prepareStatement("select * from Book");            returnCode += "\n\n- 'select * from Book' is executed successfully...";            // A table of data representing a database result set, which is            // usually generated by executing a statement that queries the            // database.            ResultSet rs = stmt.executeQuery();            while (rs.next()) {                returnCode += ("\n\ntitle:\t" + rs.getString("title"));                if (rs.getString("title").equals(receivedJson.getString("title"))) {                    returnCode += "\t-that's it!";                }                else {                    returnCode += ("\t-not the one I'm finding..." + rs.getString("title"));                }            }        }        catch (SQLException e) {            // TODO Auto-generated catch block            e.printStackTrace();        } catch (JSONException e) {            // TODO Auto-generated catch block            e.printStackTrace();        }        finally {            // Close Statement and Connection            if (stmt != null) {                try {                    stmt.close();                } catch (SQLException e) {                    // TODO Auto-generated catch block                    e.printStackTrace();                }            }            if (conn != null) {                try {                    conn.close();                } catch (SQLException e) {                    // TODO Auto-generated catch block                    e.printStackTrace();                }            }        }        return Response.status(200).entity(returnCode).build();    }    @GET    @Produces(MediaType.TEXT_PLAIN)    public String sayPlainTextHello() {        String returnCode = "this is a test~";        return returnCode;    }}

port 3306为mysql默认的端口，另外我将这边的流程和搜索过程以returnCode返回client

修改客户端

• 写一个小的json文件作为输入，如：

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{    "title":"Stardust"}

• 如果和之前的文件不是同一个，修改clientInputStream变量
• 我将in.readLine()的内容，即server返回的returCode收集后返回如下：

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