ankushs92

public class DateUtils{
	/*
	* Converts java.util.Date object to a java.time.LocalDate
	* Things are so much more convenient now!
	*/
	public static LocalDate asLocalDate(final Date date){
	    return Instant.ofEpochMilli(date.getTime()).atZone(ZoneId.systemDefault()).toLocalDate();
	}
	
	/*

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public class SomeInterceptor extends HandlerInterceptorAdapter{
    @Override
  	public boolean preHandle(final HttpServletRequest request,final HttpServletResponse response,final Object handler)
  		throws Exception
  		{
      	      /*Assume the URI is user/{userId}/post/{postId} and our interceptor is registered for this URI.
      	       * This map would then be a map of two elements,with keys 'userId' and 'postId'
      	       */
  	  	 final Map<String, String> pathVariables = (Map<String, String>) request
  	  		                                                                .getAttribute(HandlerMapping.URI_TEMPLATE_VARIABLES_ATTRIBUTE);

ankushs92

// Jwt requires an authentication on every request.Assuming that you are storing your User objects in a relational database like MySQL,
// and that your API gets moderate traffic,it is not a good idea to fetch the User object directly from the database every time.
//Instead,once it is retreived ,we cache it locally using Spring Caching abstraction.The cache backend is Google guava.

public class UserServiceImpl implements UserService { //Which further extends UserDetailsService .

  @Override
	@Cacheable(cacheNames=CacheConstants.USER_CACHE,key="#username") // We cache this  guy by its username.
	public UserDetails loadUserByUsername(final String username) throws UsernameNotFoundException {
  		final User user = userRepository.findOneByEmail(username);

ankushs92

public class NumberUtils{
  
    public boolean isNullOrZero(final Number number){
      return number == null ||
			   (
			    number instanceof Integer ? number.intValue() == 0 : 
				  number instanceof Long    ? number.longValue() == 0 :
			    number instanceof Double  ? number.doubleValue() == 0 :
			    number instanceof Short   ? number.shortValue() == 0 :
				  number.floatValue() == 0

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		// Format : dd-MM-yyyy HH:mm 
		// Use case : LocalDateTime object to Json serialization.
		final LocalDateTime dateTime = LocalDateTime.now() ; //or something else.
		final int day = dateTime.getDayOfMonth();
		final int month = dateTime.getMonthValue();
		final int year = dateTime.getYear();
		final int hour = dateTime.getHour();
		final int minute = dateTime.getMinute();
		jsonGenerator.writeString(new StringBuilder()
					.append(day).append("-")

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import java.sql.Timestamp;
import java.time.LocalDateTime;

import javax.persistence.AttributeConverter;
import javax.persistence.Converter;

@Converter(autoApply = true)
public class LocalDateTimeConverter implements AttributeConverter<LocalDateTime, Timestamp> {
    @Override
    public Timestamp convertToDatabaseColumn(LocalDateTime ldt) {

ankushs92

public class EnumUtils {
	
	public static <T extends Enum<T>> T getEnumFromString(final Class<T> enumClass,final String value) {
		    if(enumClass == null){
		       throw new IllegalArgumentException("enumClass cannot be null");
		    }
		
        for (final Enum<?> enumValue : enumClass.getEnumConstants()) {
            if (enumValue.toString().equalsIgnoreCase(value)) {

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import java.io.IOException;

import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;

public class JsonUtils {
	private static final ObjectMapper objMapper = new ObjectMapper();

	public static <T> T toObject(final String json , final Class<T> clazz) throws Exception{

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public class PreCondition {
	
	public static <T> void  checkNull(final T  t, final String errorMsg){
		if(t==null){
			throw new IllegalArgumentException(errorMsg);
		}
	}
	public static void  checkEmptyString(final String str, final String errorMsg){
		if(!Strings.hasText(str)){
			throw new IllegalArgumentException(errorMsg);

ankushs92

# Directories #
/build/
bin/
repos/
/repos/
doc/
/doc/
.gradle/
/bin/
target/