gaspersic/java-design-patterns
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

added intercepting filter

Browse Source
This commit is contained in:
Josh 2015-04-04 04:54:56 +08:00
parent f753d68d1b
commit 6d4e47311a
14 changed files with 310 additions and 289 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
README.md
View File

@ -430,7 +430,7 @@ Presentation Tier patterns are the top-most level of the application, this is co
## <a name="intercepting-filter">Intercepting Filter</a> [&#8593;](#list-of-design-patterns) ## <a name="intercepting-filter">Intercepting Filter</a> [&#8593;](#list-of-design-patterns)
**Intent:** Provide pluggable filters to conduct necessary pre-processing and post-processing to requests from a client to a target **Intent:** Provide pluggable filters to conduct necessary pre-processing and post-processing to requests from a client to a target
![alt text](https://github.com/joshzambales/java-design-patterns/blob/master/intercepting-filter/etc/Intercepting-filter.png "Intercepting Filter") ![alt text](https://github.com/iluwatar/java-design-patterns/blob/master/intercepting-filter/etc/Intercepting-filter.png "Intercepting Filter")
**Applicability:** Use the Intercepting Filter pattern when **Applicability:** Use the Intercepting Filter pattern when
* a system uses pre-processing or post-processing requests * a system uses pre-processing or post-processing requests

90
intercepting-filter/pom.xml
View File

@ -1,74 +1,18 @@
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0"
<modelVersion>4.0.0</modelVersion> xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<modelVersion>4.0.0</modelVersion>
<groupId>com.iluwatar</groupId> <parent>
<artifactId>java-design-patterns</artifactId> <groupId>com.iluwatar</groupId>
<version>1.0-SNAPSHOT</version> <artifactId>java-design-patterns</artifactId>
<packaging>pom</packaging> <version>1.0-SNAPSHOT</version>
</parent>
<properties> <artifactId>intercepting-filter</artifactId>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <dependencies>
</properties> <dependency>
<modules> <groupId>junit</groupId>
<module>abstract-factory</module> <artifactId>junit</artifactId>
<module>builder</module> <scope>test</scope>
<module>factory-method</module> </dependency>
<module>prototype</module> </dependencies>
<module>singleton</module>
<module>adapter</module>
<module>bridge</module>
<module>composite</module>
<module>decorator</module>
<module>facade</module>
<module>flyweight</module>
<module>proxy</module>
<module>chain</module>
<module>command</module>
<module>interpreter</module>
<module>iterator</module>
<module>mediator</module>
<module>memento</module>
<module>model-view-presenter</module>
<module>observer</module>
<module>state</module>
<module>strategy</module>
<module>template-method</module>
<module>visitor</module>
<module>double-checked-locking</module>
<module>servant</module>
<module>service-locator</module>
<module>null-object</module>
<module>event-aggregator</module>
<module>callback</module>
<module>execute-around</module>
<module>property</module>
</modules>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency>
</dependencies>
</dependencyManagement>
<build>
<plugins>
<!-- Tell maven to compile using Java 1.7 -->
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.0</version>
<configuration>
<source>1.7</source>
<target>1.7</target>
</configuration>
</plugin>
</plugins>
</build>
</project> </project>

14
intercepting-filter/src/main/AddressFilter.java Normal file
View File

@ -0,0 +1,14 @@
/**
* Concrete implementation of filter
*
* @author joshzambales
*
*/
public class AddressFilter implements Filter{
public String execute(String[] request){
if(request[2].equals("")){
return null;
}else return request[2];
}
}

221
intercepting-filter/src/main/App.java
View File

@ -3,6 +3,13 @@ import javax.swing.*;
import javax.swing.table.*; import javax.swing.table.*;
import java.awt.*; import java.awt.*;
import java.awt.event.*; import java.awt.event.*;
/**
*
* This is an app that checks whether the order request is valid through pre-processing done via Filters
* Each field has its own corresponding Filter
* @author joshzambales
*
*/
public class App{ public class App{
public static void main(String[] args){ public static void main(String[] args){
FilterManager filterManager = new FilterManager(new Target()); FilterManager filterManager = new FilterManager(new Target());
@ -17,229 +24,15 @@ public class App{
} }
} }
interface Filter{
public String execute(String[] request);
}
class NameFilter implements Filter{
public String execute(String[] request){
if(request[0].equals("") || request[0].matches(".*[^\\w|\\s]+.*")){
return null;
}else return request[0];
}
}
class ContactFilter implements Filter{
public String execute(String[] request){
if(request[1].equals("") || request[1].matches(".*[^\\d]+.*") || request[1].length() != 11){
return null;
}else return request[1];
}
}
class AddressFilter implements Filter{
public String execute(String[] request){
if(request[2].equals("")){
return null;
}else return request[2];
}
}
class DepositFilter implements Filter{
public String execute(String[] request){
if(request[3].equals("")){
return null;
}else return request[3];
}
}
class OrderFilter implements Filter{
public String execute(String[] request){
if(request[4].equals("")){
return null;
}else return request[4];
}
}
class Target extends JFrame{
JTable jt;
JScrollPane jsp;
DefaultTableModel dtm;
JButton del;
public Target(){
super("Order System");
setDefaultCloseOperation(EXIT_ON_CLOSE);
setSize(640,480);
dtm = new DefaultTableModel(new Object[]{"Name", "Contact Number", "Address", "Deposit Number", "Order"},0);
jt = new JTable(dtm);
del = new JButton("Delete");
setup();
}
private void setup(){
setLayout(new BorderLayout());
JPanel bot = new JPanel();
add(jt.getTableHeader(), BorderLayout.NORTH);
bot.setLayout(new BorderLayout());
bot.add(del, BorderLayout.EAST);
add(bot, BorderLayout.SOUTH);
jsp = new JScrollPane(jt);
jsp.setPreferredSize(new Dimension(500,250));
add(jsp, BorderLayout.CENTER);
del.addActionListener(new DListener());
JRootPane rootPane = SwingUtilities.getRootPane(del);
rootPane.setDefaultButton(del);
setVisible(true);
}
public void execute(String[] request){
//System.out.println(request[4]);
dtm.addRow(new Object[]{request[0],request[1],request[2],request[3],request[4]});
}
class DListener implements ActionListener{
@Override
public void actionPerformed(ActionEvent e){
int temp = jt.getSelectedRow();
if(temp == -1) return;
int temp2 = jt.getSelectedRowCount();
for(int i = 0; i < temp2; i++){
dtm.removeRow(temp);
}
}
}
}
class FilterChain{
private ArrayList<Filter> filters = new ArrayList<Filter>();
private Target target;
public void addFilter(Filter filter){
filters.add(filter);
}
public String execute(String request){
String tempout[] = new String[filters.size()];
String tempin[] = request.split("&");
int i = 0;
try{
for(Filter filter:filters){
tempout[i] = null;
tempout[i++] = filter.execute(tempin);
//System.out.println(tempout[i]);
}
}catch(Exception e){
return "NOT ENOUGHT INPUT";
}
if(tempout[4] == null){
return "INVALID ORDER!";
}else if(tempout[3] == null){
return "INVALID DEPOSIT NUMBER!";
}else if(tempout[2] == null){
return "INVALID ADRDESS!";
}else if(tempout[1] == null){
return "INVALID Contact Number!";
}else if(tempout[0] == null){
return "INVALID Name!";
}else{
target.execute(tempout);
return "RUNNING...";
}
}
public void setTarget(Target target){
this.target = target;
}
}
class FilterManager{
FilterChain filterChain;
public FilterManager(Target target){
filterChain = new FilterChain();
filterChain.setTarget(target);
}
public void setFilter(Filter filter){
filterChain.addFilter(filter);
}
public String filterRequest(String request){
return filterChain.execute(request);
}
}
class Client extends JFrame{
FilterManager filterManager;
JLabel jl;
JTextField[] jtfarr;
JTextArea[] jtaarr;
JButton[] buttarr;
public Client(){
super("Client System");
setDefaultCloseOperation(EXIT_ON_CLOSE);
setSize(300,300);
jl = new JLabel("RUNNING...");
jtfarr = new JTextField[3];
for(int i = 0; i < 3; i++){
jtfarr[i] = new JTextField();
}
jtaarr = new JTextArea[2];
for(int i = 0; i < 2; i++){
jtaarr[i] = new JTextArea();
}
buttarr = new JButton[2];
buttarr[0] = new JButton("Clear");
buttarr[1] = new JButton("Process");
setup();
}
private void setup(){
setLayout(new BorderLayout());
JPanel panel = new JPanel();
add(jl,BorderLayout.SOUTH);
add(panel, BorderLayout.CENTER);
panel.setLayout(new GridLayout(6,2));
panel.add(new JLabel("Name"));
panel.add(jtfarr[0]);
panel.add(new JLabel("Contact Number"));
panel.add(jtfarr[1]);
panel.add(new JLabel("Address"));
panel.add(jtaarr[0]);
panel.add(new JLabel("Deposit Number"));
panel.add(jtfarr[2]);
panel.add(new JLabel("Order"));
panel.add(jtaarr[1]);
panel.add(buttarr[0]);
panel.add(buttarr[1]);
buttarr[0].addActionListener(new ActionListener(){
@Override
public void actionPerformed(ActionEvent e){
for(JTextArea i : jtaarr){
i.setText("");
}
for(JTextField i : jtfarr){
i.setText("");
}
}
});
buttarr[1].addActionListener(new ActionListener(){
@Override
public void actionPerformed(ActionEvent e){
jl.setText(sendRequest(jtfarr[0].getText()+"&"+jtfarr[1].getText()+"&"+jtaarr[0].getText()+"&"+jtfarr[2].getText()+"&"+jtaarr[1].getText()));
}
});
JRootPane rootPane = SwingUtilities.getRootPane(buttarr[1]);
rootPane.setDefaultButton(buttarr[1]);
setVisible(true);
}
public void setFilterManager(FilterManager filterManager){
this.filterManager = filterManager;
}
public String sendRequest(String request){
return filterManager.filterRequest(request);
}
}

86
intercepting-filter/src/main/Client.java Normal file
View File

@ -0,0 +1,86 @@
import java.util.*;
import javax.swing.*;
import javax.swing.table.*;
import java.awt.*;
import java.awt.event.*;
/**
* The Client class is responsible for handling the input and running them through filters inside the filterManager
*
* This is where Filters come to play as the client pre-processes the request before being displayed in the Target
*
* @author joshzambales
*
*/
public class Client extends JFrame{
FilterManager filterManager;
JLabel jl;
JTextField[] jtFields;
JTextArea[] jtAreas;
JButton clearButton, processButton;
public Client(){
super("Client System");
setDefaultCloseOperation(EXIT_ON_CLOSE);
setSize(300,300);
jl = new JLabel("RUNNING...");
jtFields = new JTextField[3];
for(int i = 0; i < 3; i++){
jtFields[i] = new JTextField();
}
jtAreas = new JTextArea[2];
for(int i = 0; i < 2; i++){
jtAreas[i] = new JTextArea();
}
clearButton = new JButton("Clear");
processButton = new JButton("Process");
setup();
}
private void setup(){
setLayout(new BorderLayout());
JPanel panel = new JPanel();
add(jl,BorderLayout.SOUTH);
add(panel, BorderLayout.CENTER);
panel.setLayout(new GridLayout(6,2));
panel.add(new JLabel("Name"));
panel.add(jtFields[0]);
panel.add(new JLabel("Contact Number"));
panel.add(jtFields[1]);
panel.add(new JLabel("Address"));
panel.add(jtAreas[0]);
panel.add(new JLabel("Deposit Number"));
panel.add(jtFields[2]);
panel.add(new JLabel("Order"));
panel.add(jtAreas[1]);
panel.add(clearButton);
panel.add(processButton);
clearButton.addActionListener(new ActionListener(){
@Override
public void actionPerformed(ActionEvent e){
for(JTextArea i : jtAreas){
i.setText("");
}
for(JTextField i : jtFields){
i.setText("");
}
}
});
processButton.addActionListener(new ActionListener(){
@Override
public void actionPerformed(ActionEvent e){
jl.setText(sendRequest(jtFields[0].getText()+"&"+jtFields[1].getText()+"&"+jtAreas[0].getText()+"&"+jtFields[2].getText()+"&"+jtAreas[1].getText()));
}
});
JRootPane rootPane = SwingUtilities.getRootPane(processButton);
rootPane.setDefaultButton(processButton);
setVisible(true);
}
public void setFilterManager(FilterManager filterManager){
this.filterManager = filterManager;
}
public String sendRequest(String request){
return filterManager.filterRequest(request);
}
}

13
intercepting-filter/src/main/ContactFilter.java Normal file
View File

@ -0,0 +1,13 @@
/**
* Concrete implementation of filter
*
* @author joshzambales
*
*/
public class ContactFilter implements Filter{
public String execute(String[] request){
if(request[1].equals("") || request[1].matches(".*[^\\d]+.*") || request[1].length() != 11){
return null;
}else return request[1];
}
}

13
intercepting-filter/src/main/DepositFilter.java Normal file
View File

@ -0,0 +1,13 @@
/**
* Concrete implementation of filter
*
* @author joshzambales
*
*/
public class DepositFilter implements Filter{
public String execute(String[] request){
if(request[3].equals("")){
return null;
}else return request[3];
}
}

8
intercepting-filter/src/main/Filter.java Normal file
View File

@ -0,0 +1,8 @@
/**
* Filter interface
* @author joshzambales
*
*/
public interface Filter{
public String execute(String[] request);
}

48
intercepting-filter/src/main/FilterChain.java Normal file
View File

@ -0,0 +1,48 @@
import java.util.*;
/**
* Filter Chain carries multiple filters and help to execute them in defined order on target.
*
* @author joshzambales
*/
public class FilterChain{
private ArrayList<Filter> filters = new ArrayList<Filter>();
private Target target;
public FilterChain(Target target){
this.target = target;
}
public void addFilter(Filter filter){
filters.add(filter);
}
public String execute(String request){
String tempout[] = new String[filters.size()];
String tempin[] = request.split("&");
int i = 0;
try{
for(Filter filter:filters){
tempout[i] = null;
tempout[i++] = filter.execute(tempin);
}
}catch(Exception e){
return "NOT ENOUGHT INPUT";
}
if(tempout[4] == null){
return "INVALID ORDER!";
}else if(tempout[3] == null){
return "INVALID DEPOSIT NUMBER!";
}else if(tempout[2] == null){
return "INVALID ADRDESS!";
}else if(tempout[1] == null){
return "INVALID Contact Number!";
}else if(tempout[0] == null){
return "INVALID Name!";
}else{
target.execute(tempout);
return "RUNNING...";
}
}
}

23
intercepting-filter/src/main/FilterManager.java Normal file
View File

@ -0,0 +1,23 @@
import java.util.*;
import javax.swing.*;
import javax.swing.table.*;
import java.awt.*;
import java.awt.event.*;
/**
* Filter Manager manages the filters and Filter Chain.
* @author joshzambales
*
*/
public class FilterManager{
FilterChain filterChain;
public FilterManager(Target target){
filterChain = new FilterChain(target);
}
public void setFilter(Filter filter){
filterChain.addFilter(filter);
}
public String filterRequest(String request){
return filterChain.execute(request);
}
}

7
intercepting-filter/src/main/NameFilter.java Normal file
View File

@ -0,0 +1,7 @@
public class NameFilter implements Filter{
public String execute(String[] request){
if(request[0].equals("") || request[0].matches(".*[^\\w|\\s]+.*")){
return null;
}else return request[0];
}
}

13
intercepting-filter/src/main/OrderFilter.java Normal file
View File

@ -0,0 +1,13 @@
/**
* Concrete implementation of filter
*
* @author joshzambales
*
*/
public class OrderFilter implements Filter{
public String execute(String[] request){
if(request[4].equals("")){
return null;
}else return request[4];
}
}

58
intercepting-filter/src/main/Target.java Normal file
View File

@ -0,0 +1,58 @@
import java.util.*;
import javax.swing.*;
import javax.swing.table.*;
import java.awt.*;
import java.awt.event.*;
/**
* This is where the requests are displayed after being validated by filters.
*
* @author mjoshzambales
*
*/
public class Target extends JFrame{
JTable jt;
JScrollPane jsp;
DefaultTableModel dtm;
JButton del;
public Target(){
super("Order System");
setDefaultCloseOperation(EXIT_ON_CLOSE);
setSize(640,480);
dtm = new DefaultTableModel(new Object[]{"Name", "Contact Number", "Address", "Deposit Number", "Order"},0);
jt = new JTable(dtm);
del = new JButton("Delete");
setup();
}
private void setup(){
setLayout(new BorderLayout());
JPanel bot = new JPanel();
add(jt.getTableHeader(), BorderLayout.NORTH);
bot.setLayout(new BorderLayout());
bot.add(del, BorderLayout.EAST);
add(bot, BorderLayout.SOUTH);
jsp = new JScrollPane(jt);
jsp.setPreferredSize(new Dimension(500,250));
add(jsp, BorderLayout.CENTER);
del.addActionListener(new DListener());
JRootPane rootPane = SwingUtilities.getRootPane(del);
rootPane.setDefaultButton(del);
setVisible(true);
}
public void execute(String[] request){
dtm.addRow(new Object[]{request[0],request[1],request[2],request[3],request[4]});
}
class DListener implements ActionListener{
@Override
public void actionPerformed(ActionEvent e){
int temp = jt.getSelectedRow();
if(temp == -1) return;
int temp2 = jt.getSelectedRowCount();
for(int i = 0; i < temp2; i++){
dtm.removeRow(temp);
}
}
}
}

1
pom.xml
View File

@ -41,6 +41,7 @@
<module>null-object</module> <module>null-object</module>
<module>event-aggregator</module> <module>event-aggregator</module>
<module>callback</module> <module>callback</module>
<module>intercepting-filter</module>
</modules> </modules>
<dependencyManagement> <dependencyManagement>