Topics

import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;
import java.net.*;

/** An applet that reads a value from a TextField,
* then uses it to build three distinct URLs with embedded
* GET data: one each for Google, Infoseek, and Lycos.
* The browser is directed to retrieve each of these
* URLs, displaying them in side-by-side frame cells.
* Note that standard HTML forms cannot automatically
* perform multiple submissions in this manner.
*/

public class SearchApplet extends Applet
implements ActionListener {
private TextField queryField;
private Button submitButton;

public void init() {
    setBackground(Color.white);
    setFont(new Font("Serif", Font.BOLD, 18));
    add(new Label("Search String:"));
    queryField = new TextField(40);
    queryField.addActionListener(this);
    add(queryField);
    submitButton = new Button("Send to Search Engines");
    submitButton.addActionListener(this);
    add(submitButton);
}

/** Submit data when button is pressed <B>or</B>
   * user presses Return in the TextField.
   */

public void actionPerformed(ActionEvent event) {
    String query = URLEncoder.encode(queryField.getText());
    SearchSpec[] commonSpecs = SearchSpec.getCommonSpecs();
    // Omitting HotBot (last entry), as they use JavaScript to
    // pop result to top-level frame. Thus the length-1 below.
    for(int i=0; i<commonSpecs.length-1; i++) {
      try {
        SearchSpec spec = commonSpecs[i];
        // The SearchSpec class builds URLs of the
        // form needed by some common search engines.
        URL searchURL = new URL(spec.makeURL(query, "10"));
        String frameName = "results" + i;
        getAppletContext().showDocument(searchURL, frameName);
      } catch(MalformedURLException mue) {}
    }
}
}

/** Small class that encapsulates how to construct a
* search string for a particular search engine.
*/

public class SearchSpec {
private String name, baseURL, numResultsSuffix;

private static SearchSpec[] commonSpecs =
    { new SearchSpec("google",
                     "http://www.google.com/search?q=",
                     "&num="),
      new SearchSpec("infoseek",
                     "http://infoseek.go.com/Titles?qt=",
                     "&nh="),
      new SearchSpec("lycos",
                     "http://lycospro.lycos.com/cgi-bin/" +
                        "pursuit?query=",
                     "&maxhits="),
      new SearchSpec("hotbot",
                     "http://www.hotbot.com/?MT=",
                     "&DC=")
    };

public SearchSpec(String name,
                    String baseURL,
                    String numResultsSuffix) {
    this.name = name;
    this.baseURL = baseURL;
    this.numResultsSuffix = numResultsSuffix;
}

public String makeURL(String searchString,
                        String numResults) {
    return(baseURL + searchString +
           numResultsSuffix + numResults);
}

public String getName() {
return(name);
}

public static SearchSpec[] getCommonSpecs() {
return(commonSpecs);
}
}

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE>Search Applet Frame</TITLE>
</HEAD>

<BODY BGCOLOR="WHITE">
<CENTER>
<APPLET CODE="SearchApplet.class" WIDTH=600 HEIGHT=100>
<B>This example requires a Java-enabled browser.</B>
</APPLET>
</CENTER>
</BODY>
</HTML>