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Based on Oracle database, for example, introduced the use of JSP technology in the development of Web applications, a simple generic form of data storage approach, so as to reduce the workload of development, at the same time provides a key code.

Introduction

J2EE (Java 2 EntERPrise Edition) technology has been widely used in Web application development, the JavaBean, Servlet technologies for developers to provide a more clear development environment, the use of the technical performance of the JSP page, use the Servlet technology to deal with a large amount of business, Bean used to store data and handle some business. WEB in the applications, data storage business to the database processing often very heavy, one of the main form is in the form of data storage to the database, the whole application process involves a large number of such data storage operations, each table One must separate the preparation of the data storage procedures, the developers spent a lot of time and effort. The methods adopted to alleviate the form of data storage development work is worth studying.

Two common forms of data storage method

1, each form is the preparation of the code

In the JavaBean or JSP or Servlet page, use the request. Getparameter () function to submit one by one form of data extraction, or preparation of the JavaBean, the use of setProperty method will automatically check data to the JavaBean, and then generates SQL statements (insert, update, delete), the implementation of the final executeupdate () function to complete the data storage table.

2, data for each table automatically generate a JavaBean code

Database system to support users to read the table structure, and identify keyword section. The use of object-oriented rapid development tools, such as PowerBuilder, Delphi and so on, developed a java program code automatically generated. In the process of reading the structure of the database table: field names, data types, data length, and automatically generate a JavaBean code. The code defined in the table with the field corresponding to the variables of the same name, set up all the variables and getValue method setValue, the establishment of insert, update, delete function to deal with each insert, update, delete the formation and implementation of the SQL statement.

In the form submitted by the data-processing page, following the preparation of the code will form the data storage JavaBean:

<jsp:useBean Id="table" class="table1_bean" />

<jsp:setProperty Name="table" property="*" />

(Note: table1_bean for the above-mentioned automatically generated a corresponding list of JavaBean)

Table1_bean and then call in the insert, update, delete function to complete the data storage table and return the results. Such as:

<% Boolean success = table.insert ();%>

The first method is simple and intuitive, but each form requires the preparation of the corresponding data-processing procedures. For a little bigger application form may be a lot of volume, the development of the heavy workload, the development of low efficiency. Such as changes in the structure of the table, reducing the field, the need to amend the corresponding data-processing procedures.

The second method is relatively simple and much more the first, each table of data-processing data from the corresponding JavaBean to achieve, JavaBean automatically without the need to prepare, changes in the structure of the table only when the re-formation of a new JavaBean, compiled by the java coverage Java to the former category. However, the need to develop methods of automatically generated JavaBean procedures, changes in the structure of the table when the JavaBean need to re-generate and compile.

A simple way to achieve common form of data storage

WEB in application development, a lot of form in front through a simple browser-side data validation, submitted to the background servers, data servers do not have any direct dealing with the data stored in a data table. This situation, we can only write a program, these form a unified processing, data storage corresponding to a data table. This method is the same database system to support the request form and structure of the keyword paragraph to read identification. JSP technology we use to prepare the program, the program file named DbdataStore.jsp.

1, call format

Page in the form of Action call as follows:

<Form Name=Frm1 Method=Post Action="DBdataStore.jsp? tablename=table1&OperType=…">

table1 data to be stored in a database table of the table, OperType operation is divided into three types: insert, update, delete.

In the form of <input type=text name=…>, <textarea name=…> <select name=…> such as the name and value of the data tables were the same field, DBdataStore.jsp extracted one by one in the form submitted to the The field names correspond to the value of the data, if not defined in the form input values to be null, the field does not deal with.

2, as an example of the oracle in order to view the definition of

1) the establishment of the table data type view

CREATE OR REPLACE VIEW v_dbstru AS SELECT table_name, column_name, data_type, data_length, data_precision, data_scale, column_id

FROM all_tab_columns WHERE owner = 'user1'; / / user1 to be the main data table.

2) the establishment of a key column table view

CREATE OR REPLACE VIEW v_pkey_column AS

SELECT b.table_name, b.column_name, b.position

FROM all_constraints a, all_cons_columns b

WHERE a.owner = b.owner AND a.constraint_name = b.constraint_name AND a.owner = 'user1' AND a.constraint_type = 'P';