AMM SDK Updates

src/main/java/org/stellar/sdk/Asset.java

@@ -4,7 +4,7 @@
  * Base Asset class.
  * @see <a href="https://www.stellar.org/developers/learn/concepts/assets.html" target="_blank">Assets</a>
  */
-public abstract class Asset {
+public abstract class Asset implements Comparable<Asset> {
   Asset() {}
 
   /**
@@ -32,6 +32,13 @@ public static Asset create(String type, String code, String issuer) {
     }
   }
 
+  public static Asset create(ChangeTrustAsset.Wrapper wrapped) {
+    return wrapped.getAsset();
+  }
+  public static Asset create(TrustLineAsset.Wrapper wrapped) {
+    return wrapped.getAsset();
+  }
+
   /**
    * Creates one of AssetTypeCreditAlphaNum4 or AssetTypeCreditAlphaNum12 object based on a <code>code</code> length
    * @param code Asset code
@@ -75,6 +82,7 @@ public static Asset fromXdr(org.stellar.sdk.xdr.Asset xdr) {
    *   <li><code>native</code></li>
    *   <li><code>credit_alphanum4</code></li>
    *   <li><code>credit_alphanum12</code></li>
+   *   <li><code>pool_share</code></li>
    * </ul>
    */
   public abstract String getType();
@@ -86,4 +94,6 @@ public static Asset fromXdr(org.stellar.sdk.xdr.Asset xdr) {
    * Generates XDR object from a given Asset object
    */
   public abstract org.stellar.sdk.xdr.Asset toXdr();
+
+  public abstract int compareTo(Asset other);
 }

src/main/java/org/stellar/sdk/AssetAmount.java

@@ -0,0 +1,37 @@
+package org.stellar.sdk;
+
+import com.google.common.base.Objects;
+
+public final class AssetAmount {
+  private final Asset asset;
+  private final String amount;
+
+  AssetAmount(Asset asset, String amount) {
+    this.asset = asset;
+    this.amount = amount;
+  }
+
+  public Asset getAsset() {
+    return this.asset;
+  }
+
+  public String getAmount() {
+    return this.amount;
+  }
+
+
+  public int hashCode() {
+    return Objects.hashCode(asset, amount);
+  }
+
+  @Override
+  public boolean equals(Object object) {
+    if (!(object instanceof AssetAmount)) {
+      return false;
+    }
+
+    AssetAmount o = (AssetAmount) object;
+    return Objects.equal(this.getAsset(), o.getAsset()) &&
+            Objects.equal(this.getAmount(), o.getAmount());
+  }
+}

src/main/java/org/stellar/sdk/AssetTypeCreditAlphaNum12.java

@@ -29,12 +29,27 @@ public String getType() {
   public org.stellar.sdk.xdr.Asset toXdr() {
     org.stellar.sdk.xdr.Asset xdr = new org.stellar.sdk.xdr.Asset();
     xdr.setDiscriminant(AssetType.ASSET_TYPE_CREDIT_ALPHANUM12);
-    org.stellar.sdk.xdr.Asset.AssetAlphaNum12 credit = new org.stellar.sdk.xdr.Asset.AssetAlphaNum12();
+    org.stellar.sdk.xdr.AlphaNum12 credit = new org.stellar.sdk.xdr.AlphaNum12();
     AssetCode12 assetCode12 = new AssetCode12();
     assetCode12.setAssetCode12(Util.paddedByteArray(mCode, 12));
     credit.setAssetCode(assetCode12);
     credit.setIssuer(StrKey.encodeToXDRAccountId(mIssuer));
     xdr.setAlphaNum12(credit);
     return xdr;
   }
+
+  @Override
+  public int compareTo(Asset other) {
+    if (other.getType() != "credit_alphanum12") {
+      return 1;
+    }
+
+    AssetTypeCreditAlphaNum o = (AssetTypeCreditAlphaNum) other;
+
+    if (this.getCode() != o.getCode()) {
+      return this.getCode().compareTo(o.getCode());
+    }
+
+    return this.getIssuer().compareTo(o.getIssuer());
+  }
 }

src/main/java/org/stellar/sdk/AssetTypeCreditAlphaNum4.java

@@ -29,12 +29,29 @@ public String getType() {
   public org.stellar.sdk.xdr.Asset toXdr() {
     org.stellar.sdk.xdr.Asset xdr = new org.stellar.sdk.xdr.Asset();
     xdr.setDiscriminant(AssetType.ASSET_TYPE_CREDIT_ALPHANUM4);
-    org.stellar.sdk.xdr.Asset.AssetAlphaNum4 credit = new org.stellar.sdk.xdr.Asset.AssetAlphaNum4();
+    org.stellar.sdk.xdr.AlphaNum4 credit = new org.stellar.sdk.xdr.AlphaNum4();
     AssetCode4 assetCode4 = new AssetCode4();
     assetCode4.setAssetCode4(Util.paddedByteArray(mCode, 4));
     credit.setAssetCode(assetCode4);
     credit.setIssuer(StrKey.encodeToXDRAccountId(mIssuer));
     xdr.setAlphaNum4(credit);
     return xdr;
   }
+
+  @Override
+  public int compareTo(Asset other) {
+    if (other.getType() == "credit_alphanum12") {
+      return -1;
+    } else if (other.getType() == "native") {
+      return 1;
+    }
+
+    AssetTypeCreditAlphaNum o = (AssetTypeCreditAlphaNum) other;
+
+    if (this.getCode() != o.getCode()) {
+      return this.getCode().compareTo(o.getCode());
+    }
+
+    return this.getIssuer().compareTo(o.getIssuer());
+  }
 }

src/main/java/org/stellar/sdk/AssetTypeNative.java

@@ -40,4 +40,12 @@ public org.stellar.sdk.xdr.Asset toXdr() {
     xdr.setDiscriminant(AssetType.ASSET_TYPE_NATIVE);
     return xdr;
   }
+
+  @Override
+  public int compareTo(Asset other) {
+    if (other.getType() == "native") {
+      return 0;
+    }
+    return -1;
+  }
 }

src/main/java/org/stellar/sdk/ChangeTrustAsset.java

@@ -0,0 +1,132 @@
+package org.stellar.sdk;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * ChangeTrustAsset class.
+ * @see <a href="https://www.stellar.org/developers/learn/concepts/assets.html" target="_blank">Assets</a>
+ */
+public abstract class ChangeTrustAsset implements Comparable<ChangeTrustAsset> {
+  ChangeTrustAsset() {}
+
+  /**
+   * Parses an asset string and returns the equivalent ChangeTrustAsset instance.
+   * The asset string is expected to either be "native" or a string of the form "CODE:ISSUER"
+   *
+   * @param canonicalForm Canonical string representation of an asset
+   */
+  public static ChangeTrustAsset create(String canonicalForm) {
+    return new Wrapper(Asset.create(canonicalForm));
+  }
+
+  public static ChangeTrustAsset create(String type, String code, String issuer) {
+    return new Wrapper(Asset.create(type, code, issuer));
+  }
+  public static ChangeTrustAsset create(Asset asset) {
+    return new Wrapper(asset);
+  }
+  public static ChangeTrustAsset create(LiquidityPoolParameters params) {
+    return new LiquidityPoolShareChangeTrustAsset(params);
+  }
+  public static ChangeTrustAsset create(TrustLineAsset.Wrapper wrapper) {
+    return new Wrapper(wrapper.getAsset());
+  }
+  // Cannot convert from LiquidityPoolShareTrustLineAsset, as that only has a
+  // liquidity pool id, not parameters.
+
+  /**
+   * Creates one of AssetTypeCreditAlphaNum4 or AssetTypeCreditAlphaNum12 object based on a <code>code</code> length
+   * @param code ChangeTrustAsset code
+   * @param issuer ChangeTrustAsset issuer
+   */
+  public static ChangeTrustAsset createNonNativeAsset(String code, String issuer) {
+    return ChangeTrustAsset.create(Asset.createNonNativeAsset(code, issuer));
+  }
+
+  /**
+   * Generates ChangeTrustAsset object from a given XDR object
+   * @param xdr XDR object
+   */
+  public static ChangeTrustAsset fromXdr(org.stellar.sdk.xdr.ChangeTrustAsset xdr) {
+    // TODO: Figure out how we can re-use Asset.fromXdr here
+    String accountId;
+    switch (xdr.getDiscriminant()) {
+      case ASSET_TYPE_NATIVE:
+        return ChangeTrustAsset.create(new AssetTypeNative());
+      case ASSET_TYPE_CREDIT_ALPHANUM4:
+        String assetCode4 = Util.paddedByteArrayToString(xdr.getAlphaNum4().getAssetCode().getAssetCode4());
+        accountId = StrKey.encodeStellarAccountId(xdr.getAlphaNum4().getIssuer());
+        return ChangeTrustAsset.create(new AssetTypeCreditAlphaNum4(assetCode4, accountId));
+      case ASSET_TYPE_CREDIT_ALPHANUM12:
+        String assetCode12 = Util.paddedByteArrayToString(xdr.getAlphaNum12().getAssetCode().getAssetCode12());
+        accountId = StrKey.encodeStellarAccountId(xdr.getAlphaNum12().getIssuer());
+        return ChangeTrustAsset.create(new AssetTypeCreditAlphaNum12(assetCode12, accountId));
+      case ASSET_TYPE_POOL_SHARE:
+          return new LiquidityPoolShareChangeTrustAsset(LiquidityPoolParameters.fromXdr(xdr.getLiquidityPool()));
+      default:
+        throw new IllegalArgumentException("Unknown asset type " + xdr.getDiscriminant());
+    }
+  }
+
+  public abstract String getType();
+
+  @Override
+  public abstract boolean equals(Object object);
+
+  @Override
+  public abstract int compareTo(ChangeTrustAsset other);
+
+  /**
+   * Generates XDR object from a given ChangeTrustAsset object
+   */
+  public abstract org.stellar.sdk.xdr.ChangeTrustAsset toXdr();
+
+  public static final class Wrapper extends ChangeTrustAsset {
+    private Asset asset;
+
+    public Wrapper(Asset baseAsset) {
+      super();
+      checkNotNull(baseAsset, "asset cannot be null");
+      asset = baseAsset;
+    }
+
+    public Asset getAsset() {
+      return asset;
+    }
+
+    @Override
+    public String getType() {
+      return asset.getType();
+    }
+
+    @Override
+    public final boolean equals(Object object) {
+      if (object == null || !this.getClass().equals(object.getClass())) {
+          return false;
+      }
+
+      ChangeTrustAsset.Wrapper o = (ChangeTrustAsset.Wrapper) object;
+      return this.getAsset().equals(o.getAsset());
+    }
+
+    @Override
+    public int compareTo(ChangeTrustAsset other) {
+      if (other.getType() == "pool_share") {
+        return -1;
+      }
+      return this.getAsset().compareTo(((ChangeTrustAsset.Wrapper) other).getAsset());
+    }
+
+    @Override
+    public org.stellar.sdk.xdr.ChangeTrustAsset toXdr() {
+      org.stellar.sdk.xdr.ChangeTrustAsset xdr = new org.stellar.sdk.xdr.ChangeTrustAsset();
+
+      org.stellar.sdk.xdr.Asset assetXdr = asset.toXdr();
+      xdr.setDiscriminant(assetXdr.getDiscriminant());
+      xdr.setAlphaNum4(assetXdr.getAlphaNum4());
+      xdr.setAlphaNum12(assetXdr.getAlphaNum12());
+
+      return xdr;
+    }
+  }
+}

src/main/java/org/stellar/sdk/ChangeTrustOperation.java

@@ -14,18 +14,18 @@
  */
 public class ChangeTrustOperation extends Operation {
 
-  private final Asset asset;
+  private final ChangeTrustAsset asset;
   private final String limit;
 
-  private ChangeTrustOperation(Asset asset, String limit) {
+  private ChangeTrustOperation(ChangeTrustAsset asset, String limit) {
     this.asset = checkNotNull(asset, "asset cannot be null");
     this.limit = checkNotNull(limit, "limit cannot be null");
   }
 
   /**
    * The asset of the trustline. For example, if a gateway extends a trustline of up to 200 USD to a user, the line is USD.
    */
-  public Asset getAsset() {
+  public ChangeTrustAsset getAsset() {
     return asset;
   }
 
@@ -55,13 +55,13 @@ org.stellar.sdk.xdr.Operation.OperationBody toOperationBody(AccountConverter acc
    * @see ChangeTrustOperation
    */
   public static class Builder {
-    private final Asset asset;
+    private final ChangeTrustAsset asset;
     private final String limit;
 
     private String mSourceAccount;
 
     Builder(ChangeTrustOp op) {
-      asset = Asset.fromXdr(op.getLine());
+      asset = ChangeTrustAsset.fromXdr(op.getLine());
       limit = Operation.fromXdrAmount(op.getLimit().getInt64().longValue());
     }
 
@@ -71,7 +71,7 @@ public static class Builder {
      * @param limit The limit of the trustline. For example, if a gateway extends a trustline of up to 200 USD to a user, the limit is 200.
      * @throws ArithmeticException when limit has more than 7 decimal places.
      */
-    public Builder(Asset asset, String limit) {
+    public Builder(ChangeTrustAsset asset, String limit) {
       this.asset = checkNotNull(asset, "asset cannot be null");
       this.limit = checkNotNull(limit, "limit cannot be null");
     }