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Java

Best and Simplest ways to print Java Array

Many time printing arrays in Java are required to logging and debugging purpose. In Java provides Arrays.toString(arr) or Arrays.deepToString(arr) for arrays within arrays (a nested array) to formatting simple arrays into printable strings. Example of printing a simple array: String names[] = new String[] {“ssp”,”anu”,”kirti”,”shaurya”}; System.out.println(names); System.out.println(Arrays.toString(names)); the output of above code is given below: [Ljava.lang.String;@2a139a55 [ssp, anu, […]

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Java

Best way to prevent ArrayIndexOutOfBoundsException in Java

ArrayIndexOutOfBoundsException is an exception, thrown to indicate that an array has been accessed with an illegal index. The index is either negative or greater than or equal to the size of the array. illegal index in java is index value less than zero or -ve values and index value equal to or greater than array […]

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Java

Is Java method parameters are “pass-by-reference” or “pass-by-value”?

Many beginners think that Java is pass-by-reference. The Java specification document says that everything in Java is pass-by-value. There is no such thing as “pass-by-reference” in Java and this is fact. In Java when we pass an object to some method parameter it actually passes objects reference value which many people think that it is […]

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Java

Best way to compare strings in Java

In Java, strings are the reference type. So we can not compare two strings using the == operator as it compares references (will only return true when both references are of the same object). In Java, all objects are derived from class Object which has one method equals, which is used to compare equality of […]

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Java

What is NullPointerException in Java, and how to avoid and fix it?

In Java NullPointerExceptions are exceptions that occur when we try to use a reference that points to no location in memory (Know as null) as though it were referencing an object (uninitialized objects or assigned to null object references). Calling a method or accessing a member on a null reference will throw a NullPointerException. Generally, […]

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Java

Java Compare Two File Byte By Byte

Java example to compare two files byte by byte. We can also do this by calculating MD5 check sum.

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Java

Best Way To Compare Two Text File In Java

Java example to compare contents of two text file line by line using apache commons io library FileUtils class.

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Java

Best To Read Text File In Java

Example for best and safest way to read file to String using apache commons io library.

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Java

Best Way to Check Newer File Java

FileUtils provides six method to compare file modification time. These methods have all required checks and exception handling. For any production grade Java application it is good to use this utility as it will save effort.

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Java

Best Way to Write Strings To File In Java

In Java file writting can be done very efficiently using FileUtils class of Apache Commons IO Java library.