PropertyIgnoreCase

java.util.Properties helps to store and retrieve the key-value pair, where non-null values in key and value. This implementation made on top of java.util.HashTable. We do get all the features and APIs of HashTable additionally, getProperty(...), load() APIs.

In getProperty method, key has to be passed as argument to retrive the value. We can even specify the default value also in it, if no key found in list.

Then, What makes different in this blog posting ?. Here, the key is case-sensitive one. We have to send exact word to get the value. Most of the time, we may need to retrieve value for case-insensitive key. This is where, why don't we extend the functionality to give support to retrieve value with case-insensitive key.

Here, Properties extended to create PropertyIgnoreCase class, and added two APIs - getPropertyIgnoreCase(String key), getPropertyIgnoreCase(String key, String defaultV)

import java.util.Iterator;
import java.util.Properties;
import java.util.Set;
import java.util.Map.Entry;

public class PropertyIgnoreCase extends Properties {

 private static final long serialVersionUID = 7511088737858527084L;

 /**
  * get value from {Properties}
  * 
  * @param props
  * @param key
  * @return
  */
 public String getPropertyIgnoreCase(String key) {
  return getPropertyIgnoreCase(key, null);
 }

 /**
  * get value from {Properties}, if no key exist then return default value.
  * 
  * @param props
  * @param key
  * @param defaultV
  * @return
  */
 public String getPropertyIgnoreCase(String key, String defaultV) {
  String value = getProperty(key);
  if (null != value)
   return value;

  // Not matching with the actual key then
  Set<Entry<Object, Object>> s = entrySet();
  Iterator<Entry<Object, Object>> it = s.iterator();
  while (it.hasNext()) {
   Entry<Object, Object> entry = it.next();
   if (key.equalsIgnoreCase((String) entry.getKey())) {
    return (String) entry.getValue();
   }
  }
  return defaultV;
 }

 public static void main(String[] args) {
  PropertyIgnoreCase props = new PropertyIgnoreCase();
  props.put("Abc", "Value of Abc");
  props.put("xYZ", "Value of xYZ");

  System.out.println("get Key 'XYZ' using API from Properties = "
    + props.getProperty("XYZ"));
  System.out.println("get Key 'XYZ' using new API  = "
    + props.getPropertyIgnoreCase("XYZ"));
 }

}

Output:
get Key 'XYZ' using API from Properties = null
get Key 'XYZ' using new API  = Value of xYZ