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Quick command line spell check of a single word or sentence

Steve — Tue, 01 Sep 2009 16:43:53 +0000

Here’s a short bash script, using aspell, to spell check a word or several words from the command line. It’s simple but effective. If anyone else knows a cleaner or even simpler way, please let us know.

#!/bin/bash


WORD=$1

TEMPFILE=temp.spell

echo $WORD > $TEMPFILE aspell -c $TEMPFILE cat $TEMPFILE rm -f $TEMPFILE rm -f $TEMPFILE.bak

I named this script “spell”. Simply use it like so:
$ spell reccomend

Aspell will run and you can make your changes.
reccomend

1) recommends 6) commend 2) recommend 7) recommenced 3) reckoned recommended 4) regiment 9) Redmond 5) recombined 0) rejoined i) Ignore I) Ignore all r) Replace R) Replace all a) Add l) Add Lower b) Abort x) Exit

In this case, if I type “2″, the correction will be made, aspell will exit and the spelling I chose gets printed out.

Here’s an example of how to use it with a sentence.
$ spell "I go to the storede and buy beakh clotes"

Now aspell will take you through each misspelled word. After you finish the corrections it will exit and print out the corrected sentence or series of words.
I go to the store and buy beach clothes

Dirt Simple EXTJS Grid on Grails

Jeff — Mon, 25 Aug 2008 21:37:53 +0000

At my current contract, I’ve been using the popular EXTJS javascript library. In order to get up to speed faster, I’ve started a small project to assist my learning.

I thought about using a number of back ends to support my project, but decided on Grails after reading about the built-in JSON converters.

Getting started note: Since this is a dirt simple example, I copied extjs into the web-app/js directory. James Lorenzen looks like he has a better way, and there might be a plugin some day.

I started with a simple GORM object, Media, which looks like this:

class Media {

	static constraints = {
		releaseDate(nullable: true)
	}

	String title
	Date releaseDate
	Date dateCreated
	Date lastUpdated
}

Next I added some startup data by adding it to to Bootstrap.groovy class:

     	def m = new Media(releaseDate:null, title: 'Test')
     	m.save()

And added a controller:

import grails.converters.*

class MediaController {

    def view = {

    }

    def list = {
   	def listResult = [ total: Media.count(), items: Media.list(params)]
        render listResult as JSON
    }
}

And I now have a Grails back end that will deliver JSON to extjs! Off to the front end!

First I modified my layout, main.gsp, to add the extjs js and css files:


    
        <g:layoutTitle default="Grails" />

and added my view.gsp:


	
		
		Decorated

and lastly, my js file, taken nearly verbatim from an extjs example:

/*
 * Ext JS Library 2.0 Beta 1
 * Copyright(c) 2006-2007, Ext JS, LLC.
 * licensing@extjs.com
 *
 * http://extjs.com/license
 */

Ext.onReady(function(){

    // create the Data Store
    var ds = new Ext.data.Store({
       autoLoad: true,
       proxy: new Ext.data.HttpProxy({
       url: 'http://localhost:8080/oscar/media/list'}),
       reader: new Ext.data.JsonReader({
       	results: 'total',
       	root:'items',
       	id:'id'
       },
       [
               {name: 'title'},
               {name: 'dateCreated'},
               {name: 'lastUpdated'},
               {name: 'releaseDate'}
          ]
       )
    });

    var cm = new Ext.grid.ColumnModel([
	    {header: "Title", width: 120, dataIndex: 'title'},
		{header: "Created Date", width: 180, dataIndex: 'dateCreated'},
		{header: "Last Updated", width: 115, dataIndex: 'lastUpdated'},
		{header: "releaseDate", width: 100, dataIndex: 'releaseDate'}
	]);
    cm.defaultSortable = true;

    // create the grid
    var grid = new Ext.grid.GridPanel({
        ds: ds,
        cm: cm,
        renderTo:'center-div',
        width:540,
        height:200
    });
});

My code is checked in here.

SVN Log History By User to HTML

Jeff — Thu, 14 Aug 2008 16:25:51 +0000

Most SVN users who use the command line client understand how to create a log in XML format:

svn log --xml -v svn://some/url > svnlog.xml

But this dumps the whole log, and I really just want to see a specific user. Plus, I hate XML and definitely do not want to read it.

Here is a handy stylesheet:







        Header

Simply add a header line to your output log, like this:

Add the username you wish to filter on in the stylesheet (in place of YOUR_NAME_HERE), and open the log file in the browser.

Hat tip to:
Subversion Users mailing list
w3schools how to use xslt

A simple java.util.Date to java.sql.Date converter

Priyatam — Thu, 31 Jul 2008 15:26:39 +0000

If you’re using JSF and need a converter for converting UI elements (typically java.util.Date) to your domain object’s date field (typically java.sql.Date), here’s the code snippet,

public class DateConverter implements Converter, Serializable {
	public Object getAsObject(FacesContext context, UIComponent component, String value) {
	    java.sql.Date sqlDate = null;
	    Calendar cal = null;

	    if (value != null && value.length() > 0) {
	      DateFormat df = new SimpleDateFormat("dd-MMM-yy");

	      try {
	    	  Date utilDate = df.parse(value);
	          cal = new GregorianCalendar();
	          cal.setTime(utilDate);
	    	  sqlDate = new java.sql.Date(utilDate.getTime());
	      }
	      catch (ParseException e) {
	        throw new ConverterException(e);
	      }
	    }
	    return sqlDate;
	  }

	  public String getAsString(FacesContext context, UIComponent component, Object value) {
	    String dateString = null;
	    if (value != null) {
	      if (value instanceof String) {
	        dateString = (String) value;
	      }
	      else {
	        DateFormat df = new SimpleDateFormat("dd-MMM-yy");
	        if (value instanceof java.sql.Date) {
	        	Date date = new Date(((java.sql.Date)value).getTime());
	 	        dateString = df.format(date);
	        }
	      }
	    }
	     return dateString;
	  }
}

Extending Hibernate Validator for BigDecimal Range validation

Priyatam — Wed, 04 Jun 2008 14:22:59 +0000

Hibernate Validator is a very precise framework written in the hibernate umbrella of frameworks. Using the inbuilt validators should solve most of your column constraints. However, if you have Decimal types (Float, Double of BigDecimal), there is no inbuilt validator to validate both the precision and scale. Also, I’ve stopped using Doubles and Floats in bargain with BigDecimal as:-
1) BigDecimal has better control over math functions
2) It generates the correct column type, is Number(precison, scale) in most databases when used with hbm2ddl Tool

I’ve written two classes for validating the range (minimum and maximum) of BigDecimal types, extending HibernateValidator. It’s as good as annotating like this, for your property

 @BigDecimalRange(minPrecision=0, maxPrecision=13, scale=2)
 	public BigDecimal getFoo() {
 		return this.foo;
 }

BigDecimalRange

import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

import java.lang.annotation.Documented;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;

import org.hibernate.validator.ValidatorClass;

/**
 * The annotated element has to be in the appropriate range. Apply on BigDecimal values.
 */
@Documented
@ValidatorClass(BigDecimalRangeValidator.class)
@Target({METHOD, FIELD})
@Retention(RUNTIME)
public @interface BigDecimalRange {
	long minPrecision() default Long.MIN_VALUE;
	long maxPrecision() default Long.MAX_VALUE;
	int scale() default 0;

	String message() default "precision must be in the range of {minPrecision} to {maxPrecision} with scale<= {scale}";
}

BigDecimalRangeValidator

import java.io.Serializable;
import java.math.BigDecimal;
import org.hibernate.validator.Validator;

/**
 * The value has to be in a defined range with precision & scale
 */
public class BigDecimalRangeValidator implements Validator, Serializable {;

	private long minPrecision;
	private long maxPrecision;
	private int scale;

	public void initialize(BigDecimalRange parameters) {
		minPrecision = parameters.minPrecision();
		maxPrecision = parameters.maxPrecision();
		scale = parameters.scale();
	}

	public boolean isValid(Object value) {
		if ( value == null ) return true;
		else if ( value instanceof BigDecimal ) {
			int _precision = ((BigDecimal)value).precision();
			int _scale = ((BigDecimal)value).scale();
			return (_precision >= minPrecision && _precision <= maxPrecision && _scale <= scale);
		}
		else {
			return false;
		}
	}
}

Commons StringUtils Is Your Friend

Jeff — Wed, 14 May 2008 14:34:08 +0000

I have just completed a test for a method that parses a forward-slash delimited String:

	private static final String PROJECTID_STR_1 = "";
	private static final String PROJECTID_STR_2 = "101/103/102/104/105/106/107";
	private static final String PROJECTID_STR_3 = "///103/104";
	private static final String PROJECTID_STR_4 = "a/b/102/104/105/106/107";

	@Test
	public void testParseProjectIds1() {
		List projectIdList1 =
			getViewBillingReportController().parseProjectIds(PROJECTID_STR_1);
		assertTrue(projectIdList1.size() == 0);
	}

	@Test
	public void testParseProjectIds2() {
		List projectIdList2 =
			getViewBillingReportController().parseProjectIds(PROJECTID_STR_2);
		assertTrue(projectIdList2.size() == 7);
	}

	@Test
	public void testParseProjectIds3() {
		List projectIdList3 =
			getViewBillingReportController().parseProjectIds(PROJECTID_STR_3);
		assertTrue(projectIdList3.size() == 2);
	}

	@Test
	public void testParseProjectIds4() {
		List projectIdList4 =
			getViewBillingReportController().parseProjectIds(PROJECTID_STR_4);
		assertTrue(projectIdList4.size() == 5);
	}

This test initially failed all but one of the assertions (it passed the happy path).

The initial method looked like this:

    public List parseProjectIds(String projectIdsStr) {
    	ArrayList result = new ArrayList();
    	int lastDelimiterLoc = -1;
    	boolean done = false;
    	while (!done) {
    		int delimiterLoc = projectIdsStr.indexOf('/', lastDelimiterLoc + 1);
    		if (delimiterLoc >= 0) {
    			String idStr = projectIdsStr.substring(lastDelimiterLoc + 1, delimiterLoc);
    			Integer id = new Integer(idStr);
   			result.add(id);
    			lastDelimiterLoc = delimiterLoc;
    		} else {
    			delimiterLoc = projectIdsStr.length();
    			String idStr = projectIdsStr.substring(lastDelimiterLoc + 1, delimiterLoc);
    			Integer id = new Integer(idStr);
    			result.add(id);
    			done = true;
    		}
        }
    	return result;
    }

I don’t know why the developer on this would have done it this way, since we already had Commons Lang available in the classpath. But after a quick refactoring I came up with this:

public List parseProjectIds(String projectIdsStr) {
    	ArrayList result = new ArrayList();
    	if(StringUtils.isNotBlank(projectIdsStr)) {
    		String[] parsedList = StringUtils.split(projectIdsStr, "/");
    		for( int i =0; i < parsedList.length; i++) {
    			if( StringUtils.isNotEmpty(parsedList[i])){
    				if( StringUtils.isNumeric(parsedList[i])) {
    					result.add(new Integer(parsedList[i]));
    				}
    			}
    		}
    	}
    	return result;
    }

This passed all my tests, and seems much more readable. This is how StringUtils rocks!

PS- StringUtils.isNotBlank also handles null values.

Step by Step Tutorials – DWR with Spring, Ajax – Dynamic drop down lists

Priyatam — Wed, 07 Nov 2007 21:53:49 +0000

Scenario: A simple jsp page with a standard drop down box. A Selection criteria (could be another drop down box and a couple of check boxes) to change the values in these drop down box dynamically, without submitting the page.

What you will learn:

Configure dwr.xml with spring beans
Configure application contexts for dwr beans
The basic structure of the jsp for dwr
The necessary js that executes the ajax call along with the code for rendering the new drop down values
Finally, the facade (ajax handler) in Java, for the action

1. Configure dwr.xml with spring beans

listOptionsAjaxFacade is the bean name you would want configure in Spring’s application context. The advantage of using beans and creator=”spring” here is that all your dependencies can be autowired by default with your existing Spring container. So if you have two dao dependencies in listOptionsAjaxFacade, you can now use your existing application context to resolve dependencies. Simply add autowire=”byType”. The converter=”bean” above ensures that all Types are converted to your domain object types. I assume a package structure for domain which are the only return types of my ajax handlers.

2.Configure application contexts for dwr beans



	
		This file defines DWR Ajax Facade Beans.

I assume, you already have an application context(s) for all your controller, dao, services beans etc

3.The basic structure of the jsp for dwr









// contents of your jsp




 Ascending


// other parts of jsp

As you see, include 3 js files on the top of your jsp. The js ListOptionsAjaxFacade.js is actually the name of the handler that you
will see in a moment. The button ‘refresh’ has a js handler processListOptions.

4.The necessary js that executes the ajax call along with the code for rendering the new drop down values
Add the following js in the jsp

It retrieves the values of groupBy and ascendingorder fields from the current jsp and calls the ajax method processListOptions. Once retrieved, it uses the handy dwr.util method to replace all the list options with the new values. Note the callback function(date) used for this. Dwr replaces the return call from processListOptions and puts them in data (The complete java object collection)

5.Finally, the facade (ajax handler) in Java, for the action

public class ListOptionsAjaxFacade {
      private PersonDao personDao;

      public List processListOptions(String sortBy, boolean isAscending) {
       	return personDao.getAll(sortBy, isAscending);
      }

      //setters & getters
}

Ofcourse, this is a happy-day-flow with no exception handling either in client side or server side, but you can add that later. Read the docs for DWR.
Thats it. You should now be able to retrieve the lists dynamically

Essential Reading:
Read more on dwr.util package. Just like drop down lists, you can pretty
much create any other dynamic form element. The basic structure remains the same as above. Try using scriptaculous for fancy js effects in combination with the above code. For instance, on click of Refresh, you can fade in fade out the dropdown box.
(and charge the customer an additional 8 hours for implementing the same)

Example code, sending emails using Spring SimpleMailMessage, MimeMessagePreparator and Velocity Templates

Priyatam — Mon, 05 Nov 2007 18:57:53 +0000

When I first wrote my custom Email utlity 4 years back using JavaMail, it spread well over hundred lines of code. Looking at Spring’s out of the box functionality for sending Emails with attachements & velocity templates makes you wanna feel sorry for your old code. The reference doc by Spring for Email is quite comprehensive, however if you want even simpler Email handler with custom to/from/template with spring config, here is the code. I assume a generic object called ‘DomainObject’ in your application. (All domain objects should extend this. If you use annotations, this is the way to go for domain driven development). The email utility would accept a domain object, use it’s properties like name, lastUpdatedBy, createdBy to complete the email body, the rest of which is in a velocity template. All the other beans and To/From/Host properties are set in a context file called applicationContext-mail.xml. (Another good practice, have seperate context files in your web-app).

EmailService

package com.reverttoconsole.mail;

import java.text.SimpleDateFormat;
import java.util.HashMap;
import java.util.Map;

import javax.mail.internet.MimeMessage;

import org.apache.log4j.Logger;
import org.apache.velocity.app.VelocityEngine;
import org.springframework.mail.SimpleMailMessage;
import org.springframework.mail.javamail.JavaMailSender;
import org.springframework.mail.javamail.MimeMessageHelper;
import org.springframework.mail.javamail.MimeMessagePreparator;
import org.springframework.ui.velocity.VelocityEngineUtils;

import com.reverttoconsole.common.DomainObject;

public class EmailService {
	private static final Logger logger = Logger.getLogger(EmailService.class);

	private VelocityEngine velocityEngine;
	private String velocityTemplate;
	private JavaMailSender mailSender;
	private SimpleMailMessage templateMessage;
	private Boolean isEnabled;

	public void sendMail(final DomainObject object, final String subject) throws Exception{
    	if (!isEnabled.booleanValue()) {
    		logger.warn("Mail is not enabled. Check your applicationContext-mail.xml isEnabled Settings");
    		return;
    	}

    	MimeMessagePreparator preparator = new MimeMessagePreparator() {
            public void prepare(MimeMessage mimeMessage) throws Exception {
               MimeMessageHelper message = new MimeMessageHelper(mimeMessage);
               message.setTo(templateMessage.getTo());
               message.setFrom(templateMessage.getFrom());
               message.setSubject(subject);
               Map model = new HashMap();
               model.put("object", object);
               String text = VelocityEngineUtils.mergeTemplateIntoString(
                  velocityEngine, velocityTemplate, model);
               message.setText(text, true); //true means enable html email
            }
         };
         this.mailSender.send(preparator);
    }

	public JavaMailSender getMailSender() {
		return mailSender;
	}
	public void setMailSender(JavaMailSender mailSender) {
		this.mailSender = mailSender;
	}
	public SimpleMailMessage getTemplateMessage() {
		return templateMessage;
	}
	public void setTemplateMessage(SimpleMailMessage templateMessage) {
		this.templateMessage = templateMessage;
	}
	public VelocityEngine getVelocityEngine() {
		return velocityEngine;
	}
	public void setVelocityEngine(VelocityEngine velocityEngine) {
		this.velocityEngine = velocityEngine;
	}
	public String getVelocityTemplate() {
		return velocityTemplate;
	}
	public void setVelocityTemplate(String velocityTemplate) {
		this.velocityTemplate = velocityTemplate;
	}
	public Boolean getIsEnabled() {
		return isEnabled;
	}
	public void setIsEnabled(Boolean isEnabled) {
		this.isEnabled = isEnabled;
	}
        public String getFrom() {
               return getTemplateMessage().getFrom();
        }
        public String[] getTo() {
                 return getTemplateMessage().getTo();
        }
}

applicationContext-mail.xml


	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="
    http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd">
	
		This file defines Email beans and their dependencies .
    
       

	

	



	

         
            resource.loader=class           class.resource.loader.class=org.apache.velocity.runtime.resource.loader.ClasspathResourceLoader

Velocity Template

Make sure you place this file (.vm) in the same location as the EmailService. Stick to convention. It’s easier

Hello,

The ${object.shortName} is created by ${object.createdBy} on ${object.createdDate}.

This is a system-generated notification. Please do not reply to this email.

Please contact Support with any questions.

Thank you.

That’s it. Set your email parameters, call EmailService.sendMail(..) from your controller or application code and you’re all done!

Groovy CLIBuilder In Practice

Jeff — Mon, 06 Aug 2007 15:44:25 +0000

Ok, it doesn’t get much easier than this to build a CLI:

class ContentUpdaterMain {

static void main(args) {

def cli = new CliBuilder(usage: 'java -jar contentupdater.jar -su[dh] "update name"')
cli.h(longOpt: 'help', 'usage information')
cli.u(longOpt: 'update', 'update the provided table', args: 1)
cli.s(longOpt: 'stage', 'stage the provided table', args: 1)
cli.d(longOpt: 'debug', 'run the process with debugging enabled')
def opt = cli.parse(args)
if(!opt) return

if(opt.h) cli.usage()

if( opt.d ) {
//turn on debug
}

if(opt.u) {
//do updates
}

if( opt.s ) {
// run against staging db
}
}
}

This produces the following usage output:

usage: java -jar contentupdater.jar -su[dh] "update name"
-d,--debug run the process with debugging enabled
-h,--help usage information
-s,--stage stage the provided table
-u,--update update the provided table

And all that remains is to validate the input and invoke the processes!