javatools.administrative

Class D

java.lang.Object

javatools.administrative.D

public class D
extends Object

Copyright 2016 Fabian M. Suchanek Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. This class provides convenience methods for Input/Output. Allows to do basic I/O with easy procedure calls -- nearly like in normal programming languages. Furthermore, the class provides basic set operations for EnumSets, NULL-safe comparisons and adding to maps.
Example:

 D.p("This is an easy way to write a string");
 // And this is an easy way to read one:
 String s=D.r();
 
 // Here is a cool way to print something inline
 computeProduct(factor1,(Integer)D.p(factor2));
 
 // Here are some tricks with enums
 enum T {a,b,c};
 EnumSet<T> i=D.intersection(EnumSet.of(T.a,T.b),EnumSet.of(T.b,T.c));
 EnumSet<T> u=D.union(EnumSet.of(T.a,T.b),EnumSet.of(T.b,T.c));
 
 // Here is how to compare things, even if they are NULL
 D.compare(object1, object2);
 
 // Here is how to add something to maps that contain lists
 Map<String,List<String>> string2list=new TreeMap<String,List<String>>();
 D.addKeyValue(string2list,"key","new list element",ArrayList.class); 
 // now, the map contains "key" -> [ "new list element" ]
 D.addKeyValue(string2list,"key","again a new list element",ArrayList.class);
 // now, the map contains "key" -> [ "new list element", "again a new list element" ]  

 // Here is how to add something to maps that contain integers
 Map<String,Integer> string2list=new TreeMap<String,Integer>();
 D.addKeyValue(string2list,"key",7); // map now contains "key" -> 7
 D.addKeyValue(string2list,"key",3); // map now contains "key" -> 10

 

Field Summary

Fields

Modifier and Type	Field and Description
static int	indent Indentation margin.

Constructor Summary

Constructors

Constructor and Description
D()

Method Summary

Modifier and Type	Method and Description
static <K,V,C extends Collection<V>,L extends Collection> void	addKeyValue(Map<K,C> map, K key, V value, Class<L> collectionType) Given a map that maps to collections, adds a new key/value pair or introduces the key
static <K,V extends Enum<V>> void	addKeyValue(Map<K,EnumSet<V>> map, K key, V value) Given a map that maps to EnumSets, adds a new key/value pair or introduces the key
static <K> void	addKeyValue(Map<K,Integer> map, K key, int value) Given a map that maps to integers, adds a new key/value pair or increases the counter
static <K> void	addKeyValueDbl(Map<K,Double> map, K key, double value) Given a map that maps to doubles, adds a new key/value pair or increases the counter
static <K> void	addKeyValueFlt(Map<K,Float> map, K key, float value) Given a map that maps to floats, adds a new key/value pair or increases the counter
static <K,V,C extends Collection<V>,L extends Collection> void	addKeyValues(Map<K,C> map, K key, C values, Class<L> collectionType) Given a map that maps to collections, adds a new key/value pair or introduces the key
static <E extends Comparable<E>> int	compare(E s1, E s2) Compares two things, including NULL
static int	comparePairs(Object... o) Compares pairs of comparable things (a1,a2,b1,b2,...), including NULL
static <E extends Enum<E>> boolean	containsOneOf(EnumSet<E> s1, EnumSet<E> s2) Tells whether the intersection is non-empty
static <E> boolean	equal(E s1, E s2) Returns true if two things are equal, including NULL
static boolean	equalPairs(Object... o) Compares pairs of comparable things (a1,a2,b1,b2,...) for equality, including NULL
static void	execute(String cmd, File folder) Executes a command
static void	exit() Exits with error code 0
static <K,V> V	getOr(Map<K,V> map, K key, V defValue) Returns the element of a map or a default value
static <K> int	getOrZero(Map<K,Integer> map, K key) Returns the element of a map or 0
static <K> double	getOrZeroDouble(Map<K,Double> map, K key) Returns the element of a map or 0
protected static void	i() Prints <indent> spaces
static int	indexOf(Object o, Object... os) Returns the index of a thing in an array or -1
static <E extends Enum<E>> EnumSet<E>	intersection(EnumSet<E> s1, EnumSet<E> s2) Returns the intersection of two enumsets
static <T> int	intersectionSize(Collection<T> c1, Collection<T> c2) Returns the size of the intersection
static double[]	p(double[] a) Prints an array of doubles
static int[]	p(int[] a) Prints an array of integers
static Object	p(Object... a) Prints some Objects, returns them
static <T> T	pick(Collection<T> set) Picks one element from a set or NULL
static void	pl(Object... a) Prints some Objects on one line
static Object	println(Object... a) Prints some Objects
static String	r() Reads a line from the keyboard
static String	read() Reads a line from the keyboard
static String	read(String question) Reads a long from the keyboard
static boolean	readBoolean(String question) Reads a long from the keyboard
static double	readDouble(String question) Reads a double from the keyboard
static long	readLong(String question) Reads a long from the keyboard
static <K,V extends Comparable<V>> void	setKeyValueIfGreaterThanCurrent(Map<K,V> map, K key, V value) Given a map that maps to comparable objects, sets a key to a given value iff the current value is null or smaller than the given value
static void	silentWriteln(Writer out, Object s) Writes a line silently to a writer.
static <C extends Enum<C>> boolean	smaller(Enum<C> e1, Enum<C> e2) TRUE if the first enum is before the second
static <T> List<T>	sorted(Map<T,Integer> map) Returns a sorted list of the items
static <T> List<T>	sortedDouble(Map<T,Double> map) Returns a sorted list of the items
static String	toString(Object... o) Returns a reasonable String representation of a sequence of things.
static <E extends Enum<E>> EnumSet<E>	union(EnumSet<E> s1, EnumSet<E> s2) Returns the union of two enumsets
static void	waitMS(long milliseconds) Waits for a number of milliseconds
static void	writeln(OutputStream out, Object s) Writes a line to a writer.
static void	writeln(Writer out, Object s) Writes a line to a writer.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

indent

public static int indent

Indentation margin. All methods indent their output by indent spaces

Constructor Detail

D

public D()

Method Detail

i

protected static void i()

Prints <indent> spaces

p

public static Object p(Object... a)

Prints some Objects, returns them

println

public static Object println(Object... a)

Prints some Objects

pl

public static void pl(Object... a)

Prints some Objects on one line

p

public static int[] p(int[] a)

Prints an array of integers

p

public static double[] p(double[] a)

Prints an array of doubles

r

public static String r()

Reads a line from the keyboard

read

public static String read()

Reads a line from the keyboard

read

public static String read(String question)

Reads a long from the keyboard

readBoolean

public static boolean readBoolean(String question)

Reads a long from the keyboard

readLong

public static long readLong(String question)

Reads a long from the keyboard

readDouble

public static double readDouble(String question)

Reads a double from the keyboard

waitMS

public static void waitMS(long milliseconds)

Waits for a number of milliseconds

intersection

public static <E extends Enum<E>> EnumSet<E> intersection(EnumSet<E> s1,
                                                          EnumSet<E> s2)

Returns the intersection of two enumsets

union

public static <E extends Enum<E>> EnumSet<E> union(EnumSet<E> s1,
                                                   EnumSet<E> s2)

Returns the union of two enumsets

containsOneOf

public static <E extends Enum<E>> boolean containsOneOf(EnumSet<E> s1,
                                                        EnumSet<E> s2)

Tells whether the intersection is non-empty

exit

public static void exit()

Exits with error code 0

writeln

public static void writeln(Writer out,
                           Object s)
                    throws IOException

Writes a line to a writer. Yes, this is possible

Throws:

IOException

writeln

public static void writeln(OutputStream out,
                           Object s)
                    throws IOException

Writes a line to a writer. Yes, this is possible

Throws:

IOException

silentWriteln

public static void silentWriteln(Writer out,
                                 Object s)

Writes a line silently to a writer.

execute

public static void execute(String cmd,
                           File folder)
                    throws Exception

Executes a command

Throws:

Exception

addKeyValue

public static <K,V,C extends Collection<V>,L extends Collection> void addKeyValue(Map<K,C> map,
                                                                                  K key,
                                                                                  V value,
                                                                                  Class<L> collectionType)

Given a map that maps to collections, adds a new key/value pair or introduces the key

addKeyValue

public static <K,V extends Enum<V>> void addKeyValue(Map<K,EnumSet<V>> map,
                                                     K key,
                                                     V value)

Given a map that maps to EnumSets, adds a new key/value pair or introduces the key

addKeyValues

public static <K,V,C extends Collection<V>,L extends Collection> void addKeyValues(Map<K,C> map,
                                                                                   K key,
                                                                                   C values,
                                                                                   Class<L> collectionType)

Given a map that maps to collections, adds a new key/value pair or introduces the key

addKeyValue

public static <K> void addKeyValue(Map<K,Integer> map,
                                   K key,
                                   int value)

Given a map that maps to integers, adds a new key/value pair or increases the counter

addKeyValueFlt

public static <K> void addKeyValueFlt(Map<K,Float> map,
                                      K key,
                                      float value)

Given a map that maps to floats, adds a new key/value pair or increases the counter

addKeyValueDbl

public static <K> void addKeyValueDbl(Map<K,Double> map,
                                      K key,
                                      double value)

Given a map that maps to doubles, adds a new key/value pair or increases the counter

setKeyValueIfGreaterThanCurrent

public static <K,V extends Comparable<V>> void setKeyValueIfGreaterThanCurrent(Map<K,V> map,
                                                                               K key,
                                                                               V value)

Given a map that maps to comparable objects, sets a key to a given value iff the current value is null or smaller than the given value

getOrZero

public static <K> int getOrZero(Map<K,Integer> map,
                                K key)

Returns the element of a map or 0

getOrZeroDouble

public static <K> double getOrZeroDouble(Map<K,Double> map,
                                         K key)

Returns the element of a map or 0

getOr

public static <K,V> V getOr(Map<K,V> map,
                            K key,
                            V defValue)

Returns the element of a map or a default value

sorted

public static <T> List<T> sorted(Map<T,Integer> map)

Returns a sorted list of the items

sortedDouble

public static <T> List<T> sortedDouble(Map<T,Double> map)

Returns a sorted list of the items

equal

public static <E> boolean equal(E s1,
                                E s2)

Returns true if two things are equal, including NULL

compare

public static <E extends Comparable<E>> int compare(E s1,
                                                    E s2)

Compares two things, including NULL

comparePairs

public static int comparePairs(Object... o)

Compares pairs of comparable things (a1,a2,b1,b2,...), including NULL

equalPairs

public static boolean equalPairs(Object... o)

Compares pairs of comparable things (a1,a2,b1,b2,...) for equality, including NULL

indexOf

public static int indexOf(Object o,
                          Object... os)

Returns the index of a thing in an array or -1

smaller

public static <C extends Enum<C>> boolean smaller(Enum<C> e1,
                                                  Enum<C> e2)

TRUE if the first enum is before the second

toString

public static String toString(Object... o)

Returns a reasonable String representation of a sequence of things. Handles arrays, deep arrays and NULL.

pick

public static <T> T pick(Collection<T> set)

Picks one element from a set or NULL

intersectionSize

public static <T> int intersectionSize(Collection<T> c1,
                                       Collection<T> c2)

Returns the size of the intersection