Get All URLs From a Website Using Java Code

In this post, I am going to show you a Java class using that we can get all URLs from a website URL like a web crawler.

Here goes the Java Class

1. package client;
3. import java.io.IOException;
4. import java.io.InputStream;
5. import java.io.InputStreamReader;
6. import java.io.Reader;
8. import java.net.MalformedURLException;
9. import java.net.URI;
10. import java.net.URISyntaxException;
11. import java.net.URL;
13. import java.util.Enumeration;
15. import javax.swing.text.MutableAttributeSet;
16. import javax.swing.text.html.HTML;
17. import javax.swing.text.html.HTMLEditorKit;
18. import javax.swing.text.html.parser.ParserDelegator;
20. public class GetAllUrls {
21. public GetAllUrls() {
22. super();
23. }
25. public static void main(String[] args) {
26. final String name = "http://www.awasthiashish.com";
27. Reader r = null;
29. try {
30. URL u = new URL(name);
31. InputStream in = u.openStream();
32. r = new InputStreamReader(in);
34. ParserDelegator hp = new ParserDelegator();
35. hp.parse(r, new HTMLEditorKit.ParserCallback() {
37. public void handleStartTag(HTML.Tag t, MutableAttributeSet a, int pos) {
39. if (t == HTML.Tag.A) {
40. Enumeration attrNames = a.getAttributeNames();
42. while (attrNames.hasMoreElements()) {
43. String exactUrl = "";
44. Object key = attrNames.nextElement();
45. if ("href".equals(key.toString())) {
46. exactUrl = a.getAttribute(key).toString();
48. if (!a.getAttribute(key).toString().startsWith("http://") &&
49. !a.getAttribute(key).toString().startsWith("https://")) {
51. if (a.getAttribute(key).toString().startsWith("/")) {
52. exactUrl = name + a.getAttribute(key);
53. } else {
54. exactUrl = name.concat("/").concat(a.getAttribute(key).toString());
55. }
57. URI uri;
59. try {
60. uri = new java.net.URI(exactUrl);
61. System.out.println(uri);
62. } catch (URISyntaxException e) {
63. }
66. } else {
67. URI uri;
68. try {
69. uri = new java.net.URI(exactUrl);
70. System.out.println(uri);
71. } catch (URISyntaxException e) {
72. }
73. }
74. }
75. }
76. }
77. }
78. }, true);
79. } catch (MalformedURLException e) {
80. } catch (IOException e) {
81. } finally {
83. if (r != null) {
84. try {
85. r.close();
86. } catch (IOException e) {
87. }
88. }
89. }
90. }
91. }

and output on the console

Here you can see all the URLs linked to the home page of this website

Cheer 🙂 Happy Learning

Switching ADF Skin at run time using trinidad-config.xml

 This post talks about switching ADF skin at runtime and uses a managed bean variable to change skin name at runtime. Sometimes we want to use multiple themes for our application and in that case, we need this.

Created an ADF application, 2 different skins and a page in view controller project

Learn more about creating ADF skin in JDeveloper 

This page has a button to switch between skins and an outputText. Create a variable in the managed bean to hold skin name and button action listener to change skin variable value.

Here goes the managed bean code

1. package switchadfskin.view.bean;
3. import javax.faces.application.ViewHandler;
4. import javax.faces.component.UIViewRoot;
5. import javax.faces.context.FacesContext;
6. import javax.faces.event.ActionEvent;
8. public class SwitchADFSkinBean {
9. public SwitchADFSkinBean() {
10. }
12. //Set default skin name
13. private String skinName = "RedButton";
15. public void setSkinName(String skinName) {
16. this.skinName = skinName;
17. }
19. public String getSkinName() {
20. return skinName;
21. }
23. /**Method to change skin at runtime
24. * @param actionEvent
25. */
26. public void switchSkinAction(ActionEvent actionEvent) {
27. //Change skin name
28. if (skinName.equalsIgnoreCase("RedButton")) {
29. this.setSkinName("GreenButton");
30. } else {
31. this.setSkinName("RedButton");
32. }
33. //Reload page
34. refreshPage();
35. }
37. /**Method to refresh/reload page
38. */
39. protected void refreshPage() {
40. FacesContext fctx = FacesContext.getCurrentInstance();
41. String page = fctx.getViewRoot().getViewId();
42. ViewHandler ViewH = fctx.getApplication().getViewHandler();
43. UIViewRoot UIV = ViewH.createView(fctx, page);
44. UIV.setViewId(page);
45. fctx.setViewRoot(UIV);
47. }
48. }

The next step is to change the trinidad-config.xml file, set skin-family variable to refer to its value from managed bean so that when the user changes the bean variable then skin (CSS) is updated in the application.

1. <?xml version="1.0" encoding="windows-1252"?>
2. <trinidad-config xmlns="http://myfaces.apache.org/trinidad/config">
3. <skin-family>#{SwitchADFSkinBean.skinName}</skin-family>
4. </trinidad-config>

Now run and check application

The default skin is "RedButton" so it looks like this

and on click of the button

Sample ADF Application (JDeveloper 12.1.3) - Download

Cheers 🙂 Happy Learning