OSGI and start levels

Eclipse Plug-in start levels are there to simply determine the start order of bundles.
But as a developer or end user, we should never treat or code based on the order of OSGI start levels, it's completely managed by OSGI framework.

At least as of now, I have never come across the situation where I need to modify the plugin start level to launch an eclipse or develop Eclipse RCP Applications.

References:
http://eclipsesource.com/blogs/2009/06/10/osgi-and-start-levels/

http://aaronz-sakai.blogspot.in/2009/05/osgi-system-and-bundle-start-levels.html

http://www.osgi.org/download/r4v41/r4.core.pdf

http://help.eclipse.org/indigo/index.jsp?topic=%2Forg.eclipse.platform.doc.isv%2Freference%2Fmisc%2Fruntime-options.html

From eclipse run time options:
The start-level indicates the OSGi start level at which the bundle should run. If the start-level (>0 integer) is omitted then the framework will use the default start level for the bundle.

If they do not specify a startlevel then they default to the value of osgi.bundles.defaultStartLevel. The default value of osgi.bundles.defaultStartLevel is 4

Reading an icon from icons folder in eclipse plugin project

 To access an icon from your plugin project /icons folder, you can use below code.

 Image addImage = AbstractUIPlugin.imageDescriptorFromPlugin(MyPluginActivator.PLUGIN_ID,"$nl$/icons/add.gif").createImage();

MyPluginProject

 --src

 --icons

    -add.gif

JSON Schema to Model Converter

JSON schema/Example to model converter
http://www.jsonschema2pojo.org/

This supports Jackson and Google gson JSON libraries.

JSON Viewer
http://jsonviewer.stack.hu/


Example: for my project JSON example
{
  "projectName":"TestProject",

  "properties": {
    "createdBy": "Kondal Kolipaka",
    "createdTime": "21-01-2013",
    "lastModifiedTime":"21-02-2013"
  }
}


Generated Model for above Project JSON example:

package com.kk;

import java.util.HashMap;
import java.util.Map;
import javax.annotation.Generated;
import com.fasterxml.jackson.annotation.JsonAnyGetter;
import com.fasterxml.jackson.annotation.JsonAnySetter;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonPropertyOrder;

@JsonInclude(JsonInclude.Include.NON_NULL)
@Generated("com.googlecode.jsonschema2pojo")
@JsonPropertyOrder({
"projectName",
"properties"
})
public class Project {

@JsonProperty("projectName")
private String projectName;
@JsonProperty("properties")
private Properties properties;
private Map<String, Object> additionalProperties = newHashMap<String, Object>();

@JsonProperty("projectName")
public String getProjectName() {
return projectName;
}

@JsonProperty("projectName")
public void setProjectName(String projectName) {
this.projectName = projectName;
}

@JsonProperty("properties")
public Properties getProperties() {
return properties;
}

@JsonProperty("properties")
public void setProperties(Properties properties) {
this.properties = properties;
}

@JsonAnyGetter
public Map<String, Object> getAdditionalProperties() {
return this.additionalProperties;
}

@JsonAnySetter
public void setAdditionalProperties(String name, Object value) {
this.additionalProperties.put(name, value);
}

}
-----------------------------------com.kk.Properties.java-----------------------------------

package com.kk;

import java.util.HashMap;
import java.util.Map;
import javax.annotation.Generated;
import com.fasterxml.jackson.annotation.JsonAnyGetter;
import com.fasterxml.jackson.annotation.JsonAnySetter;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonPropertyOrder;

@JsonInclude(JsonInclude.Include.NON_NULL)
@Generated("com.googlecode.jsonschema2pojo")
@JsonPropertyOrder({
"createdBy",
"createdTime",
"lastModifiedTime"
})
public class Properties {

@JsonProperty("createdBy")
private String createdBy;
@JsonProperty("createdTime")
private String createdTime;
@JsonProperty("lastModifiedTime")
private String lastModifiedTime;
private Map<String, Object> additionalProperties = newHashMap<String, Object>();

@JsonProperty("createdBy")
public String getCreatedBy() {
return createdBy;
}

@JsonProperty("createdBy")
public void setCreatedBy(String createdBy) {
this.createdBy = createdBy;
}

@JsonProperty("createdTime")
public String getCreatedTime() {
return createdTime;
}

@JsonProperty("createdTime")
public void setCreatedTime(String createdTime) {
this.createdTime = createdTime;
}

@JsonProperty("lastModifiedTime")
public String getLastModifiedTime() {
return lastModifiedTime;
}

@JsonProperty("lastModifiedTime")
public void setLastModifiedTime(String lastModifiedTime) {
this.lastModifiedTime = lastModifiedTime;
}

@JsonAnyGetter
public Map<String, Object> getAdditionalProperties() {
return this.additionalProperties;
}

@JsonAnySetter
public void setAdditionalProperties(String name, Object value) {
this.additionalProperties.put(name, value);
}

}

As we can see it also generates getAdditionalProperties(), this would be very much useful later point of time if we wanted to send some additional information without really modifying the existing structure.