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Barbara RussoSwSE - Software and Systems Engineering Research Group
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Basic Principles of analysis and testing software
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Basic principles of analysis and testing
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Sensitivity
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Sensitivity
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Example in Java
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Example in Java
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Fail fast
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Two scenarios
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/* import what you need*/public class FailFastExample{
public static void main(String[] args){Map<String,String> premiumPhone = new HashMap<String,String>();premiumPhone.put("Apple", "iPhone");premiumPhone.put("HTC", "HTC one");premiumPhone.put("Samsung","S5");Iterator iterator = premiumPhone.keySet().iterator();while (iterator.hasNext()){
System.out.println(premiumPhone.get(iterator.next()));premiumPhone.put("Sony", "Xperia Z");
}} }
Example
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iPhone Exception in thread "main" java.util.ConcurrentModificationException
at java.util.HashMap$HashIterator.nextEntry(Unknown Source)at java.util.HashMap$KeyIterator.next(Unknown Source)at FailFastExample.main(FailFastExample.java:xx)
Output
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Fail safe
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Fail safe
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/* import what you need*/public class FailSafeExample{
public static void main(String[] args{ ConcurrentHashMap<String,String> premiumPhone = new
ConcurrentHashMap<String,String>();premiumPhone.put("Apple", "iPhone");premiumPhone.put("HTC", "HTC one");premiumPhone.put("Samsung","S5");Iterator iterator = premiumPhone.keySet().iterator();while (iterator.hasNext()) {
System.out.println(premiumPhone.get(iterator.next()));premiumPhone.put("Sony", "Xperia Z"); }
}
Example
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Output
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Differences
Fail Fast Iterator Fail Safe Iterator
Throw ConcurrentModification Exception
Yes No
Clone object No Yes
Memory Overhead No Yes
Examples HashMap,Vector,ArrayList,HashSet
CopyOnWriteArrayList,ConcurrentHashMap
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Other examples in testing
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Redundancy
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Redundancy
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Examples
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Restriction
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Substituting principle
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Examples
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static void questionable(){int k; for(int i=0; i<10;i++){
if(someCondition(i)){ k=0;
} }
}
Example
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Example
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Example
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Partition
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Example
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Example
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userqueries
numericaldata
output format requests
responsesto prompts
command key input
mouse picks on menuPartitioning is basedon input conditions
Equivalence partitioning
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Visibility
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Models
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Control Flow Graphs
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Feedback
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Examples
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Examples
