URIUtils.java

/*******************************************************************************
 * Copyright (c) 2011 The Board of Trustees of the Leland Stanford Junior University
 * as Operator of the SLAC National Accelerator Laboratory.
 * Copyright (c) 2011 Brookhaven National Laboratory.
 * EPICS archiver appliance is distributed subject to a Software License Agreement found
 * in file LICENSE that is included with this distribution.
 *******************************************************************************/
package org.epics.archiverappliance.utils.ui;

import java.io.IOException;
import java.net.URI;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;

import org.apache.http.NameValuePair;
import org.apache.http.client.utils.URLEncodedUtils;

/**
 * Some utilities for parsing URI's
 * @author mshankar
 *
 */
public class URIUtils {
	/**
	 * Parse the query string of a URI (typically used in archiver config strings) and return these as a name value pair hashmap.
	 * We do not handle multiple values for the same param in this call; we simply replace previous names.
	 * @param uri URI
	 * @return HashMap Parse the query string
	 * @throws IOException    
	 */
	public static HashMap<String, String> parseQueryString(URI uri) throws IOException {
		HashMap<String, String> ret = new HashMap<String, String>();
		if(uri == null) return ret;
		List<NameValuePair> nvs = URLEncodedUtils.parse(uri, "UTF-8");
		if(nvs == null) return ret;
		for(NameValuePair nv : nvs) {
			ret.put(nv.getName(), nv.getValue());
		}
		return ret;
	}
	
	
	/**
	 * If you do expect a param to have multiple values, use this method to get all the possible values for a name.
	 * @param uri URI 
	 * @param paramName     
	 * @return multiple values of a param
	 * @throws IOException    
	 */
	public static List<String> getMultiValuedParamFromQueryString(URI uri, String paramName) throws IOException {
		LinkedList<String> ret = new LinkedList<String>();
		if(uri == null) return ret;
		List<NameValuePair> nvs = URLEncodedUtils.parse(uri, "UTF-8");
		if(nvs == null) return ret;
		for(NameValuePair nv : nvs) {
			if(nv.getName().equals(paramName)) {
				ret.add(nv.getValue());
			}
		}
		return ret;
	}
}