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Java: How to convert List to Map
...olleague about what would be the optimal way to convert List to Map in Java and if there any specific benefits of doing so.
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Should I use string.isEmpty() or “”.equals(string)?
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source code to the String class is available java2s.com/Open-Source/Java-Document/6.0-JDK-Core/lang/java/…
– David Young
Jul 24 '10 at 5:22
1
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How can I remove an element from a list?
...me="James",age=25,
interest=c("sports","music"),
lang=list(r=3,java=2,cpp=5)),
p3=list(name="Penny",age=24,
interest=c("movies","reading"),
lang=list(r=1,cpp=4,python=2)))
list.remove(devs, c("p1","p2"))
Results in:
# $p3
# $p3$name
# [1] "Penny"
#
# $p3$age
# [1] 24...
Do Java arrays have a maximum size?
Is there a limit to the number of elements a Java array can contain? If so, what is it?
9 Answers
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How to unescape HTML character entities in Java?
... more entries to the map if you need HTML 4.
package com.example;
import java.io.StringWriter;
import java.util.HashMap;
public class StringUtils {
public static final String unescapeHtml3(final String input) {
StringWriter writer = null;
int len = input.length();
int...
Relationship between hashCode and equals method in Java [duplicate]
I read in many places saying while override equals method in Java, should override hashCode method too, otherwise it is "violating the contract".
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Access to private inherited fields via reflection in Java
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This should demonstrate how to solve it:
import java.lang.reflect.Field;
class Super {
private int i = 5;
}
public class B extends Super {
public static void main(String[] args) throws Exception {
B b = new B();
Field f = b.getClass().getSuperclas...
Why can't overriding methods throw exceptions broader than the overridden method?
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In my opinion, it is a fail in the Java syntax design. Polymorphism shouldn't limit the usage of exception handling. In fact, other computer languages don't do it (C#).
Moreover, a method is overriden in a more specialiced subclass so that it is more complex ...
Where is Java's Array indexOf?
...ity class.
If the array is not sorted and is not an array of primitives:
java.util.Arrays.asList(theArray).indexOf(o)
If the array is primitives and not sorted, one should use a solution offered by one of the other answers such as Kerem Baydoğan's, Andrew McKinlay's or Mishax's. The above code...
What's the difference of strings within single or double quotes in groovy?
Is there any difference? Or just like javascript to let's input ' and " easier in strings?
2 Answers
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