What is system out print in java

Formatting

Stream objects that implement formatting are instances of either PrintWriter , a character stream class, or PrintStream , a byte stream class.

Note: The only PrintStream objects you are likely to need are System.out and System.err . (See I/O from the Command Line for more on these objects.) When you need to create a formatted output stream, instantiate PrintWriter , not PrintStream .

Like all byte and character stream objects, instances of PrintStream and PrintWriter implement a standard set of write methods for simple byte and character output. In addition, both PrintStream and PrintWriter implement the same set of methods for converting internal data into formatted output. Two levels of formatting are provided:

• print and println format individual values in a standard way.
• format formats almost any number of values based on a format string, with many options for precise formatting.

The print and println Methods

Invoking print or println outputs a single value after converting the value using the appropriate toString method. We can see this in the Root example:

Here is the output of Root :

The square root of 2 is 1.4142135623730951. The square root of 5 is 2.23606797749979.

The i and r variables are formatted twice: the first time using code in an overload of print , the second time by conversion code automatically generated by the Java compiler, which also utilizes toString . You can format any value this way, but you don’t have much control over the results.

The format Method

The format method formats multiple arguments based on a format string. The format string consists of static text embedded with format specifiers; except for the format specifiers, the format string is output unchanged.

Format strings support many features. In this tutorial, we’ll just cover some basics. For a complete description, see format string syntax in the API specification.

The Root2 example formats two values with a single format invocation:

The square root of 2 is 1.414214.

Like the three used in this example, all format specifiers begin with a % and end with a 1- or 2-character conversion that specifies the kind of formatted output being generated. The three conversions used here are:

• d formats an integer value as a decimal value.
• f formats a floating point value as a decimal value.
• n outputs a platform-specific line terminator.

Here are some other conversions:

• x formats an integer as a hexadecimal value.
• s formats any value as a string.
• tB formats an integer as a locale-specific month name.

There are many other conversions.

Except for %% and %n , all format specifiers must match an argument. If they don’t, an exception is thrown.

In the Java programming language, the \n escape always generates the linefeed character ( \u000A ). Don’t use \n unless you specifically want a linefeed character. To get the correct line separator for the local platform, use %n .

In addition to the conversion, a format specifier can contain several additional elements that further customize the formatted output. Here’s an example, Format , that uses every possible kind of element.

3.141593, +00000003.1415926536

The additional elements are all optional. The following figure shows how the longer specifier breaks down into elements.

Elements of a Format Specifier.

The elements must appear in the order shown. Working from the right, the optional elements are:

• Precision. For floating point values, this is the mathematical precision of the formatted value. For s and other general conversions, this is the maximum width of the formatted value; the value is right-truncated if necessary.
• Width. The minimum width of the formatted value; the value is padded if necessary. By default the value is left-padded with blanks.
• Flags specify additional formatting options. In the Format example, the + flag specifies that the number should always be formatted with a sign, and the 0 flag specifies that 0 is the padding character. Other flags include — (pad on the right) and , (format number with locale-specific thousands separators). Note that some flags cannot be used with certain other flags or with certain conversions.
• The Argument Index allows you to explicitly match a designated argument. You can also specify < to match the same argument as the previous specifier. Thus the example could have said: System.out.format("%f, %

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What is system out print in java

• Introduction to Java
• The complete History of Java Programming Language
• C++ vs Java vs Python
• How to Download and Install Java for 64 bit machine?
• Setting up the environment in Java
• How to Download and Install Eclipse on Windows?
• JDK in Java
• How JVM Works – JVM Architecture?
• Differences between JDK, JRE and JVM
• Just In Time Compiler
• Difference between JIT and JVM in Java
• Difference between Byte Code and Machine Code
• How is Java platform independent?

• Decision Making in Java (if, if-else, switch, break, continue, jump)
• Java if statement with Examples
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• return keyword in Java

• Object Oriented Programming (OOPs) Concept in Java
• Why Java is not a purely Object-Oriented Language?
• Classes and Objects in Java
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• Java Methods
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What is system.out.println() in java

Do you want to print something on your computer screen and are worried about how to do it? If yes! Then this write-up is going to help you in this regard. In other languages like C, or Python, we can print text using some predefined methods such as print(), printf(), etc. However, in java we have to utilize a statement instead of a method/function. It might be confusing if you are a beginner, therefore, this post will assist you in the below-listed aspects related to the System.out.println() in java:

print() and println() methods in Java

A predefined class named PrintStream provides print() and println() methods that are used to print the string/text on the console. The only difference between these methods is that the println() function shifts the cursor to the new line after printing the statement/text.

How to Access static Members in Java

In order to understand what System.out.println() means and how it works in Java? Initially, we have to understand how to access static objects.

In java, we can access the static members with the help of their class name, and a predefined method can be accessed using the instance/object of the class. Let’s consider the below syntax for a profound understanding of this concept:

What is System.out.println() in Java

Java offers a convenient statement named “System.out.println()” that can take some arguments and print them on your computer screens.

In java, the System is a built-in class created with the final keyword and belongs to the java.lang package. out is an object/instance of the Java PrintStream class and declared as a “public static final” member field in the System class, while the println() is a predefined method of the PrintStream class.

How System.out.println() works in Java

Let’s consider the below-given code snippet for a profound understanding of how system.out.println() works in java:

public class PersonExample {

public static void main ( String [ ] args ) {

System . out . println ( «Welcome to linuxhint!» ) ;

The above statement will provide the following output:

The output verified the working of the “System.out.println()” statement as it succeeded in printing the text that it took as an argument.

System.out.println() vs System.out.print()

Let’s consider the below code snippet to understand how System.out.print() and System.out.println() works in java:

public class PersonExample {

public static void main ( String [ ] args ) {

System . out . println ( «Welcome to linuxhint!» ) ;

System . out . println ( «Welcome to linuxhint!» ) ;

System . out . print ( «Java Programming» ) ;

System . out . print ( «Java Programming» ) ;

The first two statements utilized the println() method while the last two statements utilized the print() method:

The output verified that the println() method provided a line break after every statement while the print() method printed everything in a single line.

Conclusion

Java provides a useful statement named “System.out.println()” that can take some arguments and print them on the console. In java, the System is a predefined class created with the final keyword and belongs to the java.lang package. out is an object/instance of the Java PrintStream class and declared as a “public static final” member field inside the System class, while the println() is a predefined method of the PrintStream class that prints the text on the console/computer screen. This write-up explained various aspects of system.out.println() in java.

About the author

Anees Asghar

I am a self-motivated IT professional having more than one year of industry experience in technical writing. I am passionate about writing on the topics related to web development.

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