Use BigDecimal instead of Double for Assets (#183)

marvin-we · Jan 2, 2018 · cd851c7 · cd851c7
1 parent d5192f3
commit cd851c7
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Showing 3 changed files with 41 additions and 9 deletions.
diff --git a/core/src/main/java/eu/bittrade/libs/steemj/base/models/Asset.java b/core/src/main/java/eu/bittrade/libs/steemj/base/models/Asset.java
@@ -2,6 +2,8 @@
 
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.math.BigDecimal;
+import java.security.InvalidParameterException;
 
 import org.apache.commons.lang3.builder.ToStringBuilder;
 
@@ -42,7 +44,7 @@ public class Asset implements ByteTransformable {
      *            {@link eu.bittrade.libs.steemj.enums.AssetSymbolType
      *            AssetSymbolType}.
      */
-    public Asset(double amount, AssetSymbolType symbol) {
+    public Asset(BigDecimal amount, AssetSymbolType symbol) {
         this.setSymbol(symbol);
         this.setAmount(amount);
     }
@@ -106,8 +108,14 @@ public void setAmount(long amount) {
      * @param amount
      *            The amount.
      */
-    public void setAmount(double amount) {
-        this.amount = (long) (amount * Math.pow(10.0, this.getPrecision()));
+    public void setAmount(BigDecimal amount) {
+        if (amount.scale() > this.getPrecision()) {
+            throw new InvalidParameterException("The provided 'amount' has a 'scale' of " + amount.scale()
+                    + ", but needs to have a 'scale' of " + this.getPrecision() + " when " + this.getSymbol().name()
+                    + " is used as a AssetSymbolType.");
+        }
+
+        this.amount = amount.multiply(BigDecimal.valueOf(Math.pow(10, this.getPrecision()))).longValue();
     }
 
     /**
@@ -129,12 +137,13 @@ public void setSymbol(AssetSymbolType symbol) {
     }
 
     /**
-     * Transform this asset into its double representation.
+     * Transform this asset into its {@link BigDecimal} representation.
      * 
-     * @return The value of this asset in its double representation.
+     * @return The value of this asset in its {@link BigDecimal} representation.
      */
-    public Double toReal() {
-        return Double.valueOf(this.amount / Math.pow(10.0, this.getPrecision()));
+    public BigDecimal toReal() {
+        BigDecimal transformedValue = new BigDecimal(this.getAmount());
+        return transformedValue.setScale(this.getPrecision());
     }
 
     @Override

diff --git a/core/src/main/java/eu/bittrade/libs/steemj/base/models/deserializer/AssetDeserializer.java b/core/src/main/java/eu/bittrade/libs/steemj/base/models/deserializer/AssetDeserializer.java
@@ -1,6 +1,7 @@
 package eu.bittrade.libs.steemj.base.models.deserializer;
 
 import java.io.IOException;
+import java.math.BigDecimal;
 
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.core.JsonToken;
@@ -29,7 +30,7 @@ public Asset deserialize(JsonParser jasonParser, DeserializationContext deserial
                  * value for the byte representation so we transform the amount
                  * into a long value here.
                  */
-                return new Asset(Double.valueOf(assetFields[0]), AssetSymbolType.valueOf(assetFields[1]));
+                return new Asset(new BigDecimal(assetFields[0]), AssetSymbolType.valueOf(assetFields[1]));
             }
         }
 

diff --git a/core/src/test/java/eu/bittrade/libs/steemj/base/models/AssetTest.java b/core/src/test/java/eu/bittrade/libs/steemj/base/models/AssetTest.java
@@ -2,6 +2,10 @@
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.equalTo;
+import static org.junit.Assert.fail;
+
+import java.math.BigDecimal;
+import java.security.InvalidParameterException;
 
 import org.junit.Test;
 
@@ -145,11 +149,29 @@ public void testTstdAssetToByteArray() throws Exception {
     public void testAssetEqualsMethod() {
         Asset asset = new Asset(115, AssetSymbolType.SBD);
 
-        Asset sameAsset = new Asset(0.115, AssetSymbolType.SBD);
+        Asset sameAsset = new Asset(new BigDecimal("0.115"), AssetSymbolType.SBD);
 
         Asset differentAsset = new Asset(100, AssetSymbolType.STEEM);
 
         assertThat(asset.equals(sameAsset), equalTo(true));
         assertThat(sameAsset.equals(differentAsset), equalTo(false));
     }
+
+    /**
+     * Test the {@link eu.bittrade.libs.steemj.base.models.Asset} method for the
+     * VESTS asset type.
+     */
+    @Test
+    public void testAssetBigDecimalConstructor() {
+        new Asset(new BigDecimal("0.115"), AssetSymbolType.SBD);
+        new Asset(new BigDecimal("200.11"), AssetSymbolType.STEEM);
+        new Asset(new BigDecimal("2500.145111"), AssetSymbolType.VESTS);
+
+        try {
+            new Asset(new BigDecimal("0.1151"), AssetSymbolType.SBD);
+            fail();
+        } catch (InvalidParameterException e) {
+            // Expected.
+        }
+    }
 }