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Java Enum To String

Java Enums is a new feature introduced in Java 5. Using Java Enum can help define a collection of constants in a more logical and meaningful way. Using Java Enum is a fluent way of defining constants that makes things more readable and maintainable. But sometimes we also need to convert a Java Enum to String, and that is what we will show in the examples below:

Java Byte Array To String

Byte Array is a convenient data structure that has many use cases. One scenario is when serializing some object to a file, and so we need to convert object to byte array when we write to file, and convert back from byte array to objects when we read from file. Another scenario is when sending data from one machine to another. Complex data structure is converted to a byte array before sending over the network, and on the other end the byte array is converted back to the original data structure. One of the simplest type of Object that we can convert to and from byte array is a String. This post will show how to convert Java Byte Array To String that can be applied to the use cases mentioned earlier.

Java String hashCode

Hash code in Java is very important specially with the introduction of the Java Collections API. Many classes in the Collections API uses hash code as a convention. So what exactly is a hash code? It is an integer representation of a specific Object instance. The assumption is that this integer value should be the same whenever the hashCode() method is invoked on the same Object more than once during an execution of a Java application. The hashCode method must consistently provide the same value provided that no internal data used in equals is modified on the Object. We should not worry about this on Immutable objects as internal data is not change throughout it's lifetime. In addition, if two objects are equal using the equals method of the class, then the hashCode of both should return the same value. This implies that the hashCode should be based on the data used in equals method. Lastly, it is not required that two unequal Objects should have different hashCode. Since hashCode is common to all classes as it is implemented in the Object class, we will discuss on how it is implemented in the String class of Java. This post will explain and give examples on Java String HashCode.

Java String Compare

String is one of the most fundamental data structure. It is versatile and useful for many cases. This is why Strings are used in many cases instead of using more restrictive data structure. But sometimes we need to compare two or more Strings for specific programming needs. Below are som examples on how we can compare Strings in Java.

Java String To Date

String is an all around data structure for saving information because it can handle arbitrary sequence of characters. Often times, it is also used to store numeric, date, or other type of information. Sometimes we need to convert a String object to another data structure. For example, if an HTML form submits a date information to the server, each data in the form are passed as String. In this case, we would need to convert the String to Date such that other computations can be performed. For example, determining the age based on birth date and current date. Below are some ways on how we could convert a String into Date for some specific condition or method.

Java Split String Into Array Examples

Strings and Arrays are two of the most popular data type in Java and in other popular language. String are able to represent a series of characters that is viewed as a single entity. While arrays are used to hold multiple values in the most simple way. But how do we convert a String like "One,Two,Three" into an array splitting into 3 different words or string? Below are some examples on in Java on how to split String into Array.

Java String Contains Examples

It is a common scenario in programming when we wish to check if one String contains a specific substring. For example, we wish to test if the String "The quick brown fox" contains the substring "brown". The Java String class has a method contains() that can help with this case. Below are examples on how to use Java String's contains method.

Java Double To String Without Exponential Scientific Notation

When dealing with numbers that are not whole, the type double is usually used for convenience because it is primitive and has good precision. However, when a double variable is converted to String, most of the time the result is in exponential or scientific notation. Below are some examples on how to perform in Java the conversion from double to String without exponential or scientific notation.

Java Double To String 2 Decimal Places Examples

When dealing with double values in your application, it is sometimes required to convert the values into String. Below are examples on how to convert double to String in Java using two decimal places.

Java Array To String

Java objects have the toString() method to convert the instance to it's String representation. If you will try to invoke the toString() method of an Array, the result will be some weird String like [I@70f9f9d8. This does not seems logical, say for example you wish to write the String to logs. It is more useful to convert a Java Array to a String that gives human understandable results. Below are some examples on how to do that.