The use case analysis of Java Common class-random class

This article introduces the use of the random class of Java common classes, the following is the actual case, no additional text explanation, need to explain I have written in the code comments.

Import Java.util.random;public class Random1 {public static void main (string[] args) {//Two constructors of Random R1        =new Random (); Random r2=new random (120);        Creates a new random number generator with a single long seed.        System.out.println (R1.next (2)); The return value is the protection type//SYSTEM.OUT.PRINTLN (R2.next (2));        System.out.println (R1.nextboolean ());//Returns the next pseudo-random number, which is a Boolean value derived from the uniform distribution of this random number generator sequence.        System.out.println (R1.nextboolean ());        System.out.println ("+++++++++++");        Byte[] By1=new byte[5];        Byte[] By2=new byte[5];        R1.nextbytes (by1);//Generate random bytes and place them in a user-supplied byte array.        R1.nextbytes (BY2);        for (int i=0;i<by1.length;i++) {System.out.print (by1[i]+ "");        } System.out.println ();        for (int j=0;j<by2.length;j++) {System.out.print (by2[j]+ "");        } System.out.println ();        System.out.println ("+++++++++++");        Returns the next pseudo-random number, which is a double value that is evenly distributed between 0.0 and 1.0, taken from this random number generator sequence.      System.out.println (R1.nextdouble ());  System.out.println (R1.nextdouble ());        System.out.println ("+++++++++++");        Returns the next pseudo-random number, which is a float value that is evenly distributed between 0.0 and 1.0, taken from this random number generator sequence.        System.out.println (R1.nextfloat ());        System.out.println (R1.nextfloat ());        System.out.println ("+++++++++++");        Returns the next pseudo-random number, which is a double value of Gaussian ("normal") distribution taken from this random number generator sequence, with an average of 0.0 and a standard deviation of 1.0.        System.out.println (R1.nextgaussian ());        System.out.println (R1.nextgaussian ());        System.out.println ("+++++++++++");        Returns the next pseudo-random number, which is an int value that is evenly distributed in the sequence of this random number generator.        System.out.println (R1.nextint ());        System.out.println (R1.nextint ());        System.out.println ("+++++++++++");        Returns a pseudo-random number, which is an int value that is evenly distributed between 0 (inclusive) and the specified value (not included) from this random number generator sequence.        System.out.println (R1.nextint (100));        System.out.println (R1.nextint (50));        System.out.println ("+++++++++++");        Returns the next pseudo-random number, which is a Long value System.out.println (R1.nextlong ()) derived from the uniform distribution of this random number generator sequence;        System.out.println (R1.nextlong ()); R1.setseed (10);A single long seed sets the seed of this random number generator. }}

Operation Result:

Compiling Random1.java.-----------OUTPUT-----------falsefalse+++++++++++-55-112 41-78 93 54 127-93-22 120 +++++ ++++++0.69656134440266490.06445584272260563+++++++++++0.285779950.8657566+++++++++++- 0.15436582029316171.4500847476555192+++++++++++1824132073-436413982+++++++++++2921+++++++++++ 32950749682653914961387264859162260419[finished in 1.2s]

Import Java.util.random;public class Random1 {public static void main (string[] args) {//Two constructors of Random R1        =new Random (); Random r2=new random (120);        Creates a new random number generator with a single long seed.        System.out.println (R1.next (2)); The return value is the protection type//SYSTEM.OUT.PRINTLN (R2.next (2));        System.out.println (R1.nextboolean ());//Returns the next pseudo-random number, which is a Boolean value derived from the uniform distribution of this random number generator sequence.        System.out.println (R1.nextboolean ());        System.out.println ("+++++++++++");        Byte[] By1=new byte[5];        Byte[] By2=new byte[5];        R1.nextbytes (by1);//Generate random bytes and place them in a user-supplied byte array.        R1.nextbytes (BY2);        for (int i=0;i<by1.length;i++) {System.out.print (by1[i]+ "");        } System.out.println ();        for (int j=0;j<by2.length;j++) {System.out.print (by2[j]+ "");        } System.out.println ();        System.out.println ("+++++++++++");        Returns the next pseudo-random number, which is a double value that is evenly distributed between 0.0 and 1.0, taken from this random number generator sequence.      System.out.println (R1.nextdouble ());  System.out.println (R1.nextdouble ());        System.out.println ("+++++++++++");        Returns the next pseudo-random number, which is a float value that is evenly distributed between 0.0 and 1.0, taken from this random number generator sequence.        System.out.println (R1.nextfloat ());        System.out.println (R1.nextfloat ());        System.out.println ("+++++++++++");        Returns the next pseudo-random number, which is a double value of Gaussian ("normal") distribution taken from this random number generator sequence, with an average of 0.0 and a standard deviation of 1.0.        System.out.println (R1.nextgaussian ());        System.out.println (R1.nextgaussian ());        System.out.println ("+++++++++++");        Returns the next pseudo-random number, which is an int value that is evenly distributed in the sequence of this random number generator.        System.out.println (R1.nextint ());        System.out.println (R1.nextint ());        System.out.println ("+++++++++++");        Returns a pseudo-random number, which is an int value that is evenly distributed between 0 (inclusive) and the specified value (not included) from this random number generator sequence.        System.out.println (R1.nextint (100));        System.out.println (R1.nextint (50));        System.out.println ("+++++++++++");        Returns the next pseudo-random number, which is a Long value System.out.println (R1.nextlong ()) derived from the uniform distribution of this random number generator sequence;        System.out.println (R1.nextlong ()); R1.setseed (10);A single long seed sets the seed of this random number generator. }}

Operation Result:

Compiling Random1.java.-----------OUTPUT-----------falsefalse+++++++++++-55-112 41-78 93 54 127-93-22 120 +++++ ++++++0.69656134440266490.06445584272260563+++++++++++0.285779950.8657566+++++++++++- 0.15436582029316171.4500847476555192+++++++++++1824132073-436413982+++++++++++2921+++++++++++ 32950749682653914961387264859162260419[finished in 1.2s]

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