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Edit javadoc for clarity, method signature simplification

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Make revisions to javadoc for clarity, remove unnecessary phrases, and
simplify calculateNextPermutation() method arguments.
This commit is contained in:
maddiebaka
2024-03-28 22:56:17 -04:00
parent f360c538eb
commit a8796ba886
6 changed files with 20 additions and 21 deletions
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11
src/main/java/com/cleverthis/interview/DumbBruteSolver.java
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@@ -5,9 +5,9 @@ import java.util.Collections;
import java.util.stream.Stream;
/**
* Brute-forces padlock using lexicographically ordered permutation generation
* Brute-forces padlock using lexicographically ordered permutation generation.
*
* Algorithm documented at: https://en.wikipedia.org/wiki/Permutation#Generation_in_lexicographic_order
* Permutation-generation algorithm documented at: https://en.wikipedia.org/wiki/Permutation#Generation_in_lexicographic_order
*/
public class DumbBruteSolver implements SolverInterface {
@@ -29,7 +29,7 @@ public class DumbBruteSolver implements SolverInterface {
boolean isCorrect = checkPermutation(currentPermutation, padlockAdapter);
if (!isCorrect) {
boolean nextPermutationExists = calculateNextPermutation(currentPermutation, numpadSize);
boolean nextPermutationExists = calculateNextPermutation(currentPermutation);
if(!nextPermutationExists) {
return;
}
@@ -58,10 +58,11 @@ public class DumbBruteSolver implements SolverInterface {
/**
* Calculates the next permutation in lexicographic order, based on the algorithm linked on wikipedia
* @param currentPermutation The current permutation to run the algorithm on
* @param numpadSize The number of items in the set to be permuted
* @return true if next permutation successfully generated, false if permutations have been exhausted
*/
protected boolean calculateNextPermutation(Integer[] currentPermutation, int numpadSize) {
protected boolean calculateNextPermutation(Integer[] currentPermutation) {
int numpadSize = currentPermutation.length;
if(numpadSize < 2) { return false; }
//Integer k, l;

4
src/main/java/com/cleverthis/interview/IntegerLevenshtein.java
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@@ -3,7 +3,7 @@ package com.cleverthis.interview;
import org.apache.commons.text.similarity.LevenshteinDistance;
/**
* A wrapper class that holds possible padlock passcode permutations in an integer array. This class
* Holds a single possible padlock passcode permutation in an integer array. This class
* overloads the toString() method and is comparable, using its string value to calculate the levenshtein distance and
* use those distance values for sorting into a data structure.
*/
@@ -50,7 +50,7 @@ public class IntegerLevenshtein implements Comparable<IntegerLevenshtein> {
}
/**
* Overriden compareTo method that compares the calculated levenshtein distance between two IntegerLevenshtein objects
* Overridden compareTo method that compares the calculated levenshtein distance between two IntegerLevenshtein objects
* @param otherInteger the object to be compared.
* @return The levenshtein distance between the two objects.
*/

2
src/main/java/com/cleverthis/interview/PadlockAdapter.java
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@@ -1,7 +1,7 @@
package com.cleverthis.interview;
/**
* This defines the interface that padlocks must conform to.
* This defines the contract that padlocks must conform to.
* Concrete implementations will be adapted to this interface contract through concrete adapter classes.
*/
public interface PadlockAdapter {

2
src/main/java/com/cleverthis/interview/SolverInterface.java
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@@ -1,7 +1,7 @@
package com.cleverthis.interview;
/**
* Interface that defines the class signature for solver implementations
* Defines the contract for padlock-cracking solver implementations
*/
public interface SolverInterface {

8
src/main/java/com/cleverthis/interview/WriteAwareBruteSolver.java
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@@ -3,7 +3,7 @@ package com.cleverthis.interview;
import java.util.TreeSet;
/**
* This is a write-aware brute solver implementation that uses the levenshtein distance to sort passcode permutations
* A write-aware brute solver implementation that uses the levenshtein distance to sort passcode permutations
* into a tree. Walking the tree in-order (Likely a depth-first traversal internally) results in a naive nearest-neighbor
* optimization that generally performs well, but may perform poorly in some cases. Heuristic solutions exist that have
* acceptable performance, and this is a more naive heuristic implementation.
@@ -15,7 +15,7 @@ import java.util.TreeSet;
* A more advanced solution (based on Christofides, or another TSP heuristic) may result in more performance gains, but
* the performance of this nearest-neighbor solution is adequate for the keypad sizes under test. A keypad size of 9
* results in a graph of vertex-count 9!. It's unlikely performance gains from a more intelligent TSP solver would
* offset the performance cost of building a graph and optimizing traversal.
* offset the performance cost of building a graph and solving for an optimal tour.
*/
public class WriteAwareBruteSolver extends DumbBruteSolver {
@@ -66,10 +66,8 @@ public class WriteAwareBruteSolver extends DumbBruteSolver {
* @param size The number of keys on the numpad
*/
protected void createOrderedTree(int size) {
if(this.numpadSize != size) {
this.numpadSize = size;
orderedTree.clear();
}
Integer[] currentPermutation = new Integer[numpadSize];
for(int i = 0; i < numpadSize; i++) {
@@ -82,7 +80,7 @@ public class WriteAwareBruteSolver extends DumbBruteSolver {
IntegerLevenshtein levenshteinPermutation = new IntegerLevenshtein(numpadSize);
levenshteinPermutation.setIntegerData(currentPermutation);
orderedTree.add(levenshteinPermutation);
morePermutationsExist = this.calculateNextPermutation(currentPermutation, numpadSize);
morePermutationsExist = this.calculateNextPermutation(currentPermutation);
} while(morePermutationsExist);
}
}

10
src/test/java/com/cleverthis/interview/DumbBruteSolverTest.java
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@@ -43,7 +43,7 @@ public class DumbBruteSolverTest extends SolutionTestBase {
Integer[] permutation = new Integer[] {1, 2, 3, 4};
Integer[] correctPermutation = new Integer[] {1, 2, 4, 3};
dumbSolver.calculateNextPermutation(permutation, 4);
dumbSolver.calculateNextPermutation(permutation);
assertArrayEquals(permutation, correctPermutation);
}
@@ -59,7 +59,7 @@ public class DumbBruteSolverTest extends SolutionTestBase {
Integer[] correctPermutation = new Integer[] {1, 3, 2, 4};
for(int i = 0; i < 2; i++) {
dumbSolver.calculateNextPermutation(permutation, 4);
dumbSolver.calculateNextPermutation(permutation);
}
assertArrayEquals(permutation, correctPermutation);
@@ -76,7 +76,7 @@ public class DumbBruteSolverTest extends SolutionTestBase {
Integer[] correctPermutation = new Integer[] {4, 3, 2, 1};
for(int i = 0; i < 23; i++) {
dumbSolver.calculateNextPermutation(permutation, 4);
dumbSolver.calculateNextPermutation(permutation);
}
assertArrayEquals(permutation, correctPermutation);
@@ -93,10 +93,10 @@ public class DumbBruteSolverTest extends SolutionTestBase {
Integer[] permutation = new Integer[] {1, 2, 3, 4};
for(int i = 0; i < 23; i++) {
assertTrue(dumbSolver.calculateNextPermutation(permutation, 4));
assertTrue(dumbSolver.calculateNextPermutation(permutation));
}
assertFalse(dumbSolver.calculateNextPermutation(permutation, 4));
assertFalse(dumbSolver.calculateNextPermutation(permutation));
}
}