5.spring Abstract Api

Spring 프레임워크의 이해

5. Spring Abstract API

2007 Grow up to be NHN

Spring – Abstract API

Spring JDBC 를 이용할 때 개발 자들이 구현 할 부분 작업

Spring JDBC

개발자

Connection 관리

O

X

SQL

X

O

Statement 관리

O

X

ResultSet 관리

O

X

Row 데이터 추출

X

O

패러미터 선언

X

O

패러미터 Setting

O

X

트랜잭션 관리

O

X

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2007 Grow up to be NHN

Spring – Abstract API

Template Method Pattern

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Spring – Abstract API

2007 Grow up to be NHN

人

2007 Grow up to be NHN

Spring – Abstract API

public abstract class AbstractClass { public void templateMethod() { // .. 비지니스 로직 구현 operation1(); // .. 비지니스 로직 구현 operation2(); } protected abstract void operation1(); protected abstract void operation2(); }

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Spring – Abstract API

2007 Grow up to be NHN

public class ConcreteClassA extends AbstractClass { protected void operation1() { // TODO Auto-generated method stub } protected void operation2() { // TODO Auto-generated method stub } }

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Spring – Abstract API

2007 Grow up to be NHN

Template Method = IoC

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2007 Grow up to be NHN

Spring – Abstract API

Callback Class

Callback Method

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Spring – Abstract API

2007 Grow up to be NHN

public interface RowCallbackHandler { void processRow(ResultSet rs) throws SQLException; }

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Spring – Abstract API

2007 Grow up to be NHN

public void query(String sql, RowCallbackHandler callbackHandler) throws JdbcSqlException { Connection con = null; PreparedStatement ps = null; ResultSet rs = null; try { con = ps = con.prepareStatement (sql); rs = ps.executeQuery(); while (rs.next()) { callbackHandler.processRow(rs); } rs.close(); ps.close(); } catch (SQLException ex) { throw new JdbcSqlException("Couldn't run query [" + sql + "]", ex); } finally { DataSourceUtils.closeConnectionIfNecessary(this.dataSource, con); } }

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Spring – Abstract API

2007 Grow up to be NHN

class StringHandler implements JdbcTemplate.RowCallbackHandler { private List 1 = new LinkedList(); public void processRow(ResultSet rs)throws SQLException { 1.add(rs.getString(1)); } public String[] getStrings() { return (String[]) 1.toArray(new String[1.size()]); } }

StringHandler sh = new StringHandler(); jdbcTemplate.query("SELECT FORENAME FROM CUSTMR", sh); String[] forenames = sh.getStrings();

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