package org.inszy.spring.support;
 
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Collections;
import java.util.Set;
 
import org.springframework.core.convert.TypeDescriptor;
import org.springframework.core.convert.converter.ConditionalGenericConverter;
import org.springframework.core.convert.support.GenericConversionService;
import org.springframework.util.ClassUtils;
import org.springframework.util.ReflectionUtils;
 
public final class IdToEntityOrNullConveter implements ConditionalGenericConverter {
 
	private final GenericConversionService conversionService;
 
	public IdToEntityOrNullConveter(GenericConversionService conversionService) {
		this.conversionService = conversionService;
	}
 
	public Set getConvertibleTypes() {
		return Collections.singleton(new ConvertiblePair(Object.class, Object.class));
	}
 
	public boolean matches(TypeDescriptor sourceType, TypeDescriptor targetType) {
		Method finder = getFinder(targetType.getType());
		return (finder != null && this.conversionService.canConvert(sourceType, TypeDescriptor.valueOf(finder
				.getParameterTypes()[0])));
	}
 
	public Object convert(Object source, TypeDescriptor sourceType, TypeDescriptor targetType) {
		Method finder = getFinder(targetType.getType());
		Object id = this.conversionService.convert(source, sourceType, TypeDescriptor.valueOf(finder
				.getParameterTypes()[0]));
		if (id == null)
			return null;
 
		return ReflectionUtils.invokeMethod(finder, source, id);
	}
 
	private Method getFinder(Class< ?> entityClass) {
		String finderMethod = "find" + getEntityName(entityClass);
		Method[] methods = entityClass.getDeclaredMethods();
		for (Method method : methods) {
			if (Modifier.isStatic(method.getModifiers()) && method.getParameterTypes().length == 1
					&& method.getReturnType().equals(entityClass)) {
				if (method.getName().equals(finderMethod)) {
					return method;
				}
			}
		}
		return null;
	}
 
	private String getEntityName(Class< ?> entityClass) {
		String shortName = ClassUtils.getShortName(entityClass);
		int lastDot = shortName.lastIndexOf('.');
		if (lastDot != -1) {
			return shortName.substring(lastDot + 1);
		} else {
			return shortName;
		}
	}
 
}

import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.net.URL;
import java.net.URLConnection;
import java.nio.CharBuffer;
import java.util.Date;
import java.util.logging.Level;
import java.util.logging.Logger;
 
public class InternetChecker {
 
	private static final String URL_TO_CHECK = "http://www.google.com/";
	private static final long CHECK_EVERY = 30 * 60 * 1000; /* 30 minutes */
 
	private static final int BUF_SIZE = 1024;
	private static InternetChecker ref;
	private Date lastCheck;
	private Boolean lastState;
	private final Logger log = Logger.getLogger(InternetChecker.class.getName());
 
	public InternetChecker() {
	}
 
	private boolean isStateValid() {
		if (lastState == null)
			return false;
		if (lastCheck.getTime() > System.currentTimeMillis() + CHECK_EVERY)
			return false;
		return true;
	}
 
	public boolean isConnectionPresent() {
		if (!isStateValid()) {
			checkConnection();
		}
		return lastState;
	}
 
	public boolean isConnectionPresent(boolean forceCheck) {
		if (forceCheck)
			invalidateState();
		return isConnectionPresent();
	}
 
	private void invalidateState() {
		lastCheck = null;
		lastState = null;
	}
 
	public void checkConnection() {
		lastCheck = new Date();
		try {
			URL url = new URL(URL_TO_CHECK);
			URLConnection urlConnection = url.openConnection();
 
			InputStream inputStream = urlConnection.getInputStream();
			Reader reader = new InputStreamReader(inputStream);
 
			StringBuilder contents = new StringBuilder();
			CharBuffer buf = CharBuffer.allocate(BUF_SIZE);
 
			while (true) {
				reader.read(buf);
				if (!buf.hasRemaining())
					break;
 
				contents = contents.append(buf);
			}
			inputStream.close();
			lastState = true;
			log.log(Level.INFO, "Internet connectivy present.");
		} catch (Exception e) {
			log.log(Level.WARNING, "Internet connectivity not present.", e);
			lastState = false;
		}
	}
 
	public static InternetChecker getDefaultInstance() {
		if (ref == null) {
			ref = new InternetChecker();
		}
		return ref;
	}
}