Improving the BucketObject class and introducing the Converter class

src/main/java/de/bitsharesmunich/graphenej/Converter.java

@@ -0,0 +1,112 @@
+package de.bitsharesmunich.graphenej;
+
+import java.math.BigDecimal;
+
+import de.bitsharesmunich.graphenej.errors.IncompleteAssetError;
+import de.bitsharesmunich.graphenej.models.BucketObject;
+
+/**
+ * Converter class used to translate the market information contained in a BucketObject instance.
+ *
+ * Created by nelson on 12/23/16.
+ */
+public class Converter {
+    private final String TAG = this.getClass().getName();
+    public static final int OPEN_VALUE = 0;
+    public static final int CLOSE_VALUE = 1;
+    public static final int HIGH_VALUE = 2;
+    public static final int LOW_VALUE = 3;
+
+    public static final int BASE_TO_QUOTE = 100;
+    public static final int QUOTE_TO_BASE = 101;
+
+    private Asset base;
+    private Asset quote;
+    private BucketObject bucket;
+
+    public Converter(Asset base, Asset quote, BucketObject bucket){
+        this.base = base;
+        this.quote = quote;
+        this.bucket = bucket;
+    }
+
+    /**
+     * Method used to obtain the equivalence between two assets considering their precisions
+     * and given the specific time bucket passed in the constructor.
+     *
+     * The resulting double value will tell us how much of a given asset, a unit of
+     * its pair is worth.
+     *
+     * The second argument is used to specify which of the assets should
+     * be taken as a unit reference.
+     *
+     * For instance if used with the BASE_TO_QUOTE constant, this method will tell us how
+     * many of the quote asset will make up for a unit of the base asset. And the opposite
+     * is true for the QUOTE_TO_BASE contant.
+     *
+     * @param bucketAttribute: The desired bucket attribute to take in consideration. Can
+     *                       be any of the following: OPEN_VALUE, CLOSE_VALUE, HIGH_VALUE or
+     *                       LOW_VALUE.
+     * @param direction: One of two constants 'BASE_TO_QUOTE' or 'QUOTE_TO_BASE' used to specify
+     *                 which of the two assets is the one used as a unitary reference.
+     * @return: double value representing how much of one asset, a unit of the paired asset
+     * was worth at the point in time specified by the time bucket and the bucket parameter.
+     */
+    public double getConversionRate(int bucketAttribute, int direction){
+        if(this.base.getPrecision() == -1 || this.quote.getPrecision() == -1){
+            throw new IncompleteAssetError();
+        }
+        BigDecimal baseValue;
+        BigDecimal quoteValue;
+        switch (bucketAttribute){
+            case OPEN_VALUE:
+                baseValue = bucket.open_base;
+                quoteValue = bucket.open_quote;
+                break;
+            case CLOSE_VALUE:
+                baseValue = bucket.close_base;
+                quoteValue = bucket.close_quote;
+                break;
+            case HIGH_VALUE:
+                baseValue = bucket.high_base;
+                quoteValue = bucket.high_quote;
+                break;
+            case LOW_VALUE:
+                baseValue = bucket.low_base;
+                quoteValue = bucket.low_quote;
+                break;
+            default:
+                baseValue = bucket.close_base;
+                quoteValue = bucket.close_quote;
+        }
+        double basePrecisionAdjusted = baseValue.divide(BigDecimal.valueOf((long) Math.pow(10, base.getPrecision()))).doubleValue();
+        double quotePrecisionAdjusted = quoteValue.divide(BigDecimal.valueOf((long) Math.pow(10, quote.getPrecision()))).doubleValue();
+        if(direction == QUOTE_TO_BASE){
+            return basePrecisionAdjusted / quotePrecisionAdjusted;
+        }else{
+            return quotePrecisionAdjusted / basePrecisionAdjusted;
+        }
+    }
+
+    /**
+     * Converts a given asset amount to the corresponding pair used when creating this class.
+     * @param assetAmount: The asset to convert from.
+     * @param bucketAttribute: The bucket attribute to use as a reference. Possible values are OPEN_VALUE,
+     *                       CLOSE_VALUE, HIGH_VALUE or LOW_VALUE.
+     * @return: The converted value in base units, that is the number of a unit x 10^precision
+     */
+    public long convert(AssetAmount assetAmount, int bucketAttribute) {
+        double conversionRate = 0;
+        double precisionFactor = 0.0;
+        if(assetAmount.getAsset().equals(this.base)){
+            conversionRate = this.getConversionRate(bucketAttribute, BASE_TO_QUOTE);
+            precisionFactor = Math.pow(10, this.quote.getPrecision()) / Math.pow(10, this.base.getPrecision());
+        }else if(assetAmount.getAsset().equals(this.quote)){
+            conversionRate = this.getConversionRate(bucketAttribute, QUOTE_TO_BASE);
+            precisionFactor = Math.pow(10, this.base.getPrecision()) / Math.pow(10, this.quote.getPrecision());
+        }
+        long assetAmountValue = assetAmount.getAmount().longValue();
+        long convertedBaseValue = (long) (assetAmountValue * conversionRate * precisionFactor);
+        return convertedBaseValue;
+    }
+}

src/main/java/de/bitsharesmunich/graphenej/Test.java

@@ -986,7 +986,17 @@ public class Test {
                 List<BucketObject> bucketList = (List<BucketObject>) response.result;
                 if(bucketList.size() > 0){
                     BucketObject bucket = bucketList.get(0);
-                    System.out.println(String.format("bucket. high_base: %d, high_quote: %d", bucket.high_base, bucket.high_quote));
+                    Asset base = bucket.key.base;
+                    Asset quote = bucket.key.quote;
+                    base.setPrecision(5);
+                    quote.setPrecision(4);
+                    System.out.println(String.format("Base. symbol: %s, precision: %d", base.getObjectId(), base.getPrecision()));
+                    System.out.println(String.format("Quote. symbol: %s, precision: %d", quote.getObjectId(), quote.getPrecision()));
+                    Converter converter = new Converter(base, quote, bucket);
+                    double rate = converter.getConversionRate(Converter.CLOSE_VALUE, Converter.BASE_TO_QUOTE);
+                    System.out.println(String.format("Conversion rate is 1 base -> %f quote", rate));
+                    double rate2 = converter.getConversionRate(Converter.CLOSE_VALUE, Converter.QUOTE_TO_BASE);
+                    System.out.println(String.format("Conversion rate is 1 quote -> %f base", rate2));
                 }
             }
 
@@ -1011,11 +1021,11 @@ public class Test {
             cal.set(Calendar.SECOND, 0);
             cal.set(Calendar.MINUTE, 0);
 
-            Asset BTS = new Asset("1.3.0");
+            Asset USD = new Asset("1.3.121", "USD", 4);
-            Asset USD = new Asset("1.3.121");
+            Asset BTS = new Asset("1.3.0", "BTS", 5);
             long bucket = 3600;
 
-            mWebSocket.addListener(new GetMarketHistory(USD, BTS, bucket, cal.getTime(), cal.getTime(), listener));
+            mWebSocket.addListener(new GetMarketHistory(BTS, USD, bucket, cal.getTime(), cal.getTime(), listener));
             mWebSocket.connect();
         } catch (NoSuchAlgorithmException e) {
             System.out.println("NoSuchAlgorithmException. Msg: " + e.getMessage());

src/main/java/de/bitsharesmunich/graphenej/errors/IncompleteAssetError.java

@@ -0,0 +1,10 @@
+package de.bitsharesmunich.graphenej.errors;
+
+/**
+ * Created by nelson on 12/25/16.
+ */
+public class IncompleteAssetError extends RuntimeException{
+    public IncompleteAssetError(){
+        super("The asset used in this method is probably incomplete, Assets instances can be created with just its id information but this context requires more information");
+    }
+}

src/main/java/de/bitsharesmunich/graphenej/models/BucketObject.java

@@ -4,7 +4,7 @@ import com.google.gson.*;
 import de.bitsharesmunich.graphenej.Asset;
 
 import java.lang.reflect.Type;
-import java.math.BigInteger;
+import java.math.BigDecimal;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.Date;
@@ -31,16 +31,16 @@ public class BucketObject {
 
     public String id;
     public Key key;
-    public BigInteger high_base;
+    public BigDecimal high_base;
-    public BigInteger high_quote;
+    public BigDecimal high_quote;
-    public BigInteger low_base;
+    public BigDecimal low_base;
-    public BigInteger low_quote;
+    public BigDecimal low_quote;
-    public BigInteger open_base;
+    public BigDecimal open_base;
-    public BigInteger open_quote;
+    public BigDecimal open_quote;
-    public BigInteger close_base;
+    public BigDecimal close_base;
-    public BigInteger close_quote;
+    public BigDecimal close_quote;
-    public BigInteger base_volume;
+    public BigDecimal base_volume;
-    public BigInteger quote_volume;
+    public BigDecimal quote_volume;
 
     public static class Key {
         public Asset base;
@@ -55,16 +55,16 @@ public class BucketObject {
         public BucketObject deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException {
             JsonObject jsonBucket = json.getAsJsonObject();
             BucketObject bucket = new BucketObject();
-            bucket.high_base = jsonBucket.get(KEY_HIGH_BASE).getAsBigInteger();
+            bucket.high_base = jsonBucket.get(KEY_HIGH_BASE).getAsBigDecimal();
-            bucket.high_quote = jsonBucket.get(KEY_HIGH_QUOTE).getAsBigInteger();
+            bucket.high_quote = jsonBucket.get(KEY_HIGH_QUOTE).getAsBigDecimal();
-            bucket.low_base = jsonBucket.get(KEY_LOW_BASE).getAsBigInteger();
+            bucket.low_base = jsonBucket.get(KEY_LOW_BASE).getAsBigDecimal();
-            bucket.low_quote = jsonBucket.get(KEY_LOW_QUOTE).getAsBigInteger();
+            bucket.low_quote = jsonBucket.get(KEY_LOW_QUOTE).getAsBigDecimal();
-            bucket.open_base = jsonBucket.get(KEY_OPEN_BASE).getAsBigInteger();
+            bucket.open_base = jsonBucket.get(KEY_OPEN_BASE).getAsBigDecimal();
-            bucket.open_quote = jsonBucket.get(KEY_OPEN_QUOTE).getAsBigInteger();
+            bucket.open_quote = jsonBucket.get(KEY_OPEN_QUOTE).getAsBigDecimal();
-            bucket.close_base = jsonBucket.get(KEY_CLOSE_BASE).getAsBigInteger();
+            bucket.close_base = jsonBucket.get(KEY_CLOSE_BASE).getAsBigDecimal();
-            bucket.close_quote = jsonBucket.get(KEY_CLOSE_QUOTE).getAsBigInteger();
+            bucket.close_quote = jsonBucket.get(KEY_CLOSE_QUOTE).getAsBigDecimal();
-            bucket.base_volume = jsonBucket.get(KEY_BASE_VOLUME).getAsBigInteger();
+            bucket.base_volume = jsonBucket.get(KEY_BASE_VOLUME).getAsBigDecimal();
-            bucket.quote_volume = jsonBucket.get(KEY_QUOTE_VOLUME).getAsBigInteger();
+            bucket.quote_volume = jsonBucket.get(KEY_QUOTE_VOLUME).getAsBigDecimal();
             bucket.key = new Key();
             String baseId = jsonBucket.get(KEY_KEY).getAsJsonObject().get(KEY_BASE).getAsString();
             String quoteId = jsonBucket.get(KEY_KEY).getAsJsonObject().get(KEY_QUOTE).getAsString();

src/test/java/de/bitsharesmunich/graphenej/AssetTest.java

@@ -0,0 +1,19 @@
+package de.bitsharesmunich.graphenej;
+
+import org.junit.*;
+
+import static org.junit.Assert.*;
+
+/**
+ * Created by nelson on 12/24/16.
+ */
+public class AssetTest {
+
+    @org.junit.Test
+    public void equals() throws Exception {
+        Asset bts = new Asset("1.3.0");
+        Asset bitUSD = new Asset("1.3.121");
+        assertNotEquals("Different assets should not be equal", bts, bitUSD);
+    }
+
+}