'Bounded Retransmission Protocol' Blob

1 files changed, 54 insertions, 0 deletions

diff --git a/assignments/assignment2/Bounded Retransmission Protocol Tester/Source/brpcompare/HashAlphabet.java b/assignments/assignment2/Bounded Retransmission Protocol Tester/Source/brpcompare/HashAlphabet.java
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index 0000000..46742d2
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+++ b/assignments/assignment2/Bounded Retransmission Protocol Tester/Source/brpcompare/HashAlphabet.java
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+package brpcompare;
+
+import net.automatalib.words.Alphabet;
+import net.automatalib.words.abstractimpl.AbstractAlphabet;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+
+/**
+ * Created by joshua on 14/07/2016.
+ * I noticed that getSymbolIndex was called a lot. So I optimized for that, with a look up structure.
+ * Too bad it wasn't in LearnLib already.
+ */
+public class HashAlphabet<I> extends AbstractAlphabet<I> {
+    private final ArrayList<I> symbols;
+    private final HashMap<I, Integer> indices;
+
+    public HashAlphabet(Alphabet<I> in) {
+        symbols = new ArrayList<>(in);
+        indices = new HashMap<>(in.size());
+        for (int i = 0; i < symbols.size(); i++) {
+            indices.put(symbols.get(i), i);
+        }
+    }
+
+    @Override
+    public I getSymbol(int index) {
+        return symbols.get(index);
+    }
+
+    @Override
+    public int getSymbolIndex(I symbol) {
+        return indices.get(symbol);
+    }
+
+    @Override
+    public int size() {
+        return symbols.size();
+    }
+
+    /* (non-Javadoc)
+     * @see net.automatalib.words.abstractimpl.AbstractAlphabet#writeToArray(int, java.lang.Object[], int, int)
+     */
+    @Override
+    public void writeToArray(int offset, Object[] array, int tgtOfs, int num) {
+        System.arraycopy(symbols, offset, array, tgtOfs, num);
+    }
+
+    @Override
+    public boolean containsSymbol(I symbol) {
+        return indices.containsKey(symbol);
+    }
+
+}