Hack 97. Program Google in Java

Programming the Google Web API in Java is a snap, thanks to the functionality packed into the Google Web API Developer's Kit.

Thanks to the Java Archive (JAR) file included in the Google Web API Developer's Kit, programming the Google API in Java couldn't be simpler. The googleapi.jar archive includes com.google.soap.search, a nice, clean wrapper around the underlying Google SOAP, along with the Apache Software Foundation's open source Crimson (http://xml.apache.org/crimson) XML parser and Apache SOAP (http://xml.apache.org/soap/) stack, among others.

In addition to the googleapi.jar file included in the Google API Developer's Kit, you'll need a copy of the Java 2 Platform, Standard Edition (J2SE, http://java.sun.com/downloads/) to compile and run this hack.

9.14.1. The Code

Save the following code to a file called Googly.java:

// Googly.java

// Bring in the Google SOAP wrapper.

import com.google.soap.search.*;

import java.io.*;

public class Googly {

  // Your Google API developer's key.

  private static String googleKey = "insert key here"; 

  public static void main(String[] args) {

    // Make sure there's a Google query on the command line.

    if (args.length != 1) {

      System.err.println("Usage: java [-classpath classpath] Googly <query>");

      System.exit(1);

    }

    // Create a new GoogleSearch object.

    GoogleSearch s = new GoogleSearch( );

    try {

    

      s.setKey(googleKey);

      s.setQueryString(args[0]); // Google query from the command-line

      s.setMaxResults(10);

      // Query Google.

      GoogleSearchResult r = s.doSearch( );

      // Gather the results.

      GoogleSearchResultElement[] re = r.getResultElements( );

      

      // Output.

      for ( int i = 0; i < re.length; i++ ) {

     System.out.println(re[i].getTitle( ));

     System.out.println(re[i].getURL( ));

     System.out.println(re[i].getSnippet( ) + "\n");

      }

    

    // Anything go wrong?

    } catch (GoogleSearchFault f) {

      System.out.println("GoogleSearchFault: " + f.toString( ));

    }

  }

  

}

Be sure to drop in your own Google developer's key in place of insert key here, like so:

// Your Google API developer's key.

private static String googleKey = "

12BuCK13mY5h0E/34KN0cK@ttH3Do0R

";

9.14.2. Compiling the Code

To successfully compile the Googly application, you'll need that googleapi.jar archive. I chose to keep it in the same directory as my Googly.java source file; if you put it elsewhere, adjust the path after -classpath accordingly.

% javac -classpath googleapi.jar Googly.java

This should leave you with a brand new Googly.class file, ready to run.

9.14.3. Running the Hack

Run Googly on the command line ["How to Run the Hacks" in the Preface], passing it your Google query, like so under Unix and Mac OS X:

% java -classpath .:googleapi.jar Googly  "query words"

and like so under Windows (notice the ; instead of : in the classpath):

java -classpath .;googleapi.jar Googly "query words"

9.14.4. The Results

% java -classpath .:googleapi.jar Googly "Learning Java"

oreilly.com -- Online Catalog: Learning Java  

http://www.oreilly.com/catalog/learnjava/

For programmers either just migrating to Java or already working 

steadily in the forefront of Java development, Learning Java gives 

a clear, systematic   ...    

oreilly.com -- Online Catalog:   Learning     Java  , 2nd Edition

http://www.oreilly.com/catalog/learnjava2/

This new edition of Learning Java has been expanded and updated for

Java 2 Standard Edition SDK 1.4. It comprehensively addresses ...    

... 

Java Programming...From the Grounds Up / Web Developer

http://www.webdeveloper.com/java/java_programming_grounds_up.html

... WebDeveloper.com. Java Programming... From the Grounds Up. by 

Mark C. Reynolds ... Java Classes and Methods. Java utilizes the 

basic object technology found in C++. ...