Java Type vs PostgreSQL Type (六) 整數型別之對應 -short

short and Short:

測試Java Types:short and Short時，先建置一張資料表。

資料表語法:

CREATE TABLE shorttypes
(
short smallint,
short1 smallint,
id serial NOT NULL,
CONSTRAINT shorttypes_pkey PRIMARY KEY (id)
)

程式原始碼:
JavaShortType.java:

package zasax.type.numbertypes.integertypes;

import java.io.IOException;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import zasax.conn.PostgreConnection;

/**
*
* @author YiCheng,Hsiao
*/
public class JavaShortType {

private Connection conn;
private PreparedStatement pstmt;
private ResultSet rs;
private String setSQL = "Insert into shorttypes (short,short1) values (?,?)";
private String getSQL = "select * from shorttypes";

public static void main(String[] args)
throws IOException, ClassNotFoundException, SQLException {
JavaShortType jst = new JavaShortType();
short s = 32767;
short s1 = 0;
Short s2 = 0;
jst.setShortValue(s, s);
ResultSet rs = jst.getShortValue();
while(rs.next()){
s1 = rs.getShort("short");
s2 = rs.getShort("short1");
System.out.println(s1+" "+s2);
}
}

public void setShortValue(short s1, Short s2)
throws IOException, ClassNotFoundException, SQLException {
PostgreConnection pc = new PostgreConnection();
this.conn = pc.getConnection();
this.pstmt = conn.prepareStatement(setSQL);
pstmt.setShort(1, s1);
pstmt.setShort(2, s2);
pstmt.execute();
pstmt.close();
conn.close();
}

public ResultSet getShortValue()
throws IOException, ClassNotFoundException, SQLException {
PostgreConnection pc = new PostgreConnection();
this.conn = pc.getConnection();
this.pstmt = conn.prepareStatement(getSQL);
this.rs = pstmt.executeQuery();
return rs;
}
}

實際測試流程:

儲存Short值方式:
透過setShortValue(short , Short ) 這個方法，將傳入值byte b = 127分別指派給short(基本型別)，Short(外覆類別)。再將這兩個變數分別存入PostgreSQL Type : smallint 的兩個欄位(short , short1)。傳入值在資料表上有呈現資料，表示傳入成功。

讀取Short值方式:
經getShortValue()的方法，先透過executeQuery()，將SQL語法"select * from shorttypes"傳入資料庫查詢，回傳ResultSet指派給rs，再將rs回傳指派給main()區塊的ResultSet，而ResultSet保存著SQL查詢完後的資料表內容，再分別透過ResultSet將值傳回給short s1，以及Short s2，最後在印出結果32767,32767，為了確定印出值為資料庫所傳回的，在初始值上，將short s1 = 0 ， Short s2 = 0，以作為驗證其結果。

整理表格如下:

Java Types	PostgreSQL Types	特性
short	smallint	2 bytes，小範圍整數，-32768 到 +32767
Short