Processing of large text types in JDBC Java database connection 11)

1. J handling of large text types in DBC

large text data types in Oracle,

Clob Long Text type ( not supported in MySQL, using text)

Blob binary Type

MySQL Database,

Text long Text type

Blob binary Type

Requirements: manipulate long text data in JDBC.

Design: Test Table

Coding:

Saving large text data types

Reading large text data types

Saving binary data

Read binary data

Mysql:

1 -- test Big Data types 2 CREATE TABLE Test (3      INT PRIMARY KEY Auto_increment, 4      content Longtext,5     img longblob6 );

Java:

1  Public classApp_text {2     3     //Global Parameters4     PrivateConnection con;5     PrivateStatement stmt;6     PrivatePreparedStatement pstmt;7     PrivateResultSet rs;8     9 Ten @Test One     //1. Save large text data type (write Longtext) A      Public voidTestsavetext () { -String sql = "INSERT INTO Test (?)"; -         Try { the             //Connection -Con =jdbcutil.getconnection (); -             //pstmt Object -PSTMT =con.preparestatement (SQL); +             //Setting Parameters -             //get the file path First +String Path = App_text.class. GetResource ("Tips.txt"). GetPath (); AFileReader reader =NewFileReader (NewFile (path)); atPstmt.setcharacterstream (1, reader); -              -             //Execute SQL - pstmt.executeupdate (); -              -             //Close in reader.close (); -}Catch(Exception e) { to e.printstacktrace (); +}finally { -Jdbcutil.closeall (Con, pstmt,NULL); the         } *     } $     Panax Notoginseng @Test -     //2. Read the large text data type (read Longtext) the      Public voidTestgetastext () { +String sql = "SELECT * from Test;"; A         Try { the             //Connection +Con =jdbcutil.getconnection (); -             //pstmt Object $PSTMT =con.preparestatement (SQL); $             //Read -rs =pstmt.executequery (); -             if(Rs.next ()) { the                 //get long text data, Mode 1: -                 //Reader r = Rs.getcharacterstream ("content");Wuyi                  the                 //get long text data, Mode 2: -System.out.print (rs.getstring ("content")); Wu             } -              About}Catch(Exception e) { $ e.printstacktrace (); -}finally { -Jdbcutil.closeall (Con, pstmt,NULL); -         } A     } + } the  -  $ blob the  the  Public classApp_blob { the      the     //Global Parameters -     PrivateConnection con; in     PrivateStatement stmt; the     PrivatePreparedStatement pstmt; the     PrivateResultSet rs; About      the  the @Test the     //1. Binary data type (write Longblob) +      Public voidTestsavetext () { -String sql = "INSERT INTO Test (IMG) VALUES (?)"; the         Try {Bayi             //Connection theCon =jdbcutil.getconnection (); the             //pstmt Object -PSTMT =con.preparestatement (SQL); -             //Get Picture Stream theInputStream in = App_text.class. getResourceAsStream ("7.jpg"); thePstmt.setbinarystream (1, in); the              the             //Execute Save Picture - Pstmt.execute (); the              the             //Close the in.close ();94              the}Catch(Exception e) { the e.printstacktrace (); the}finally {98Jdbcutil.closeall (Con, pstmt,NULL); About         } -     }101     102 @Test103     //2. Read the large text data type (read Longblob)104      Public voidTestgetastext () { theString sql = "Select img from test where id=2;";106         Try {107             //Connection108Con =jdbcutil.getconnection ();109             //pstmt Object thePSTMT =con.preparestatement (SQL);111             //Read thers =pstmt.executequery ();113             if(Rs.next ()) { the                 //Get Picture Stream theInputStream in = Rs.getbinarystream ("img"); the                 //Picture output stream117FileOutputStream out =NewFileOutputStream (NewFile ("C://1.jpg"));118                 intLen =-1;119                 byteB[] =New byte[1024]; -                  while(len = In.read (b))! =-1) {121Out.write (b, 0, Len);122                 }123                 //Close124 out.close (); the in.close ();126             }127              -}Catch(Exception e) {129 e.printstacktrace (); the}finally {131Jdbcutil.closeall (Con, pstmt,NULL); the         }133     }134}

Processing of large text types in JDBC Java database connection 11)