java-util

Most used short code snippets generically designed. The goal is to avoid NullPointerException and IndexOutOfBoundException , still providing meaningful outputs. All the methods in this library accepts Nullables and gracefully performs alternate actions defined.

This is overall top level usage doc, detailed docs are present as javadoc within code files

Gradle:

compile 'in.yajnesh.util:java-util:1.0.0'

General Utilities

1) Safely get item from any Sequence

Friendly APIs to get item from any Sequence. It is bettet to get null instead of crashing with NullPointerException or IndexOutOfBoundException

a) JUtil.get(sequence, 5);

This will try to get 6th item from sequence.

Sequence can be any of the following

• Array
• List
• String
• CharSequence

Return value will be

• In case sequence is null, null will be returned instead of crashing
• In case of index is above the size of negative index, null will be returned instead of crashing

b) JUtil.get(array/collection, 5, defaultValue);

This is similar to the above api, but instead of null values, this will return defaultvalue provided

2) Check if an something is empty

Friendly APIs to identify if elements/sequence is empty.

JUtil.isEmpty(something);

This will return true if something is empty or null

parameter something can be any of the following

• Array
• Collection
• CharSequence
• Map
• String

Return value will be

• In case parameter is null, true will be returned instead of crashing
• In case parameter is empty(decided by underlaying datastructure) , return true
• Return false, in all other cases

3) Get the size of something

Friendly APIs to get the size of element/sequence.

JUtil.size(something);

This will return the size of something

parameter something can be any of the following

• Array
• Collection
• String
• CharSequence

Return value will be

• In case parameter is null, 0 will be returned
• if not null, then based on the underlaying datastructure, size will be returned

4) Safely get last item from any Sequence

Friendly APIs to get item from any Sequence. It is bettet to get null instead of crashing with NullPointerException or IndexOutOfBoundException

a) JUtil.getLastItem(sequence);

This will try to get last item from sequence.

Sequence can be any of the following

• Array
• List
• String
• CharSequence

Return value will be

• In case sequence is null, null will be returned instead of crashing
• In case of index is above the size of negative index, null will be returned instead of crashing

b) JUtil.getLastItem(sequence, defaultValue);

This is similar to the above api, but instead of null values, this will return defaultvalue provided

5) Equals

Compare two obects for equality

a) JUtil.equals(a,b);

This will return true if both objects are equal

parameter something can be any of the following

• Any Object

Return value will be

• In case of either parameter is null, false will be returned
• In case of both parameters are null, false will be returned
• If objects are equal , true will be returned, false otherwise

b) JUtil.equalsRelaxed(a,b);

This is similar to the above api, but ignores the cases while comparing

6) Contains

Does source has searchTerm in it?

a) JUtil.contains(source,searchTerm);

true if searchTerm is found in source, otherwise false. Also false if either or both params are null

b) JUtil.containsIgnoreCase(source,searchTerm);

This is similar to the above api, but ignores the cases while checking

7) TypeCast

TypeCast and object to passed class

JUtil.typeCast(object,Integer.class);

In this case, safely typecasts object to Integer and returns an Integer

8) Stringify

Get string out of Collection

a) JUtil.stringify(collection/map);

returns string representation of collection/map

b) JUtil.stringify(preText,collection/map);

This is similar to the above api, adds preText infront of the string representaion

9) Is Any Empty

Is any object passed is null or empty.

JUtil.isAnyEmpty(string1,string2,string3,string4);

JUtil.isAnyEmpty(collection,map,string,charSequence,object);

returns true, if any of the object passed is null or empty, false otherwise

10) Are All Empty

Are all the object passed is null or empty.

JUtil.isAllEmpty(string1,string2,string3,string4);

JUtil.isAllEmpty(collection,map,string,charSequence,object);

returns true, if all of the object passed is null or empty, false otherwise

11) Get String

Get string from given object

a) JUtil.getString(something);

This will return string representaion of the parameter

parameter something can be any of the following

• Any Object
• EditText
• TextView

Return value will be

• String contained under the object, or null

b) JUtil.getStringSafe(something);

This is same as above, but returns empty string in case input in null

12) Safe url encode

Translates a string into x-www-form-urlencoded.

JUtil.safeUrlEncode(string,encoding);

returns the encoded url

Many other classes documentation coming soon, Please look at the javadoc within the code till then