Improved exceptions.

baseline.xml

@@ -2,6 +2,7 @@
 <SmellBaseline>
   <ManuallySuppressedIssues/>
   <CurrentIssues>
-    <ID>ThrowsCount:CryptoPrice.kt$CryptoPrice.Companion$ @JvmStatic @JvmOverloads @Throws(CryptoException::class) fun apiCall(paths: List&lt;String>, params: Map&lt;String, String> = emptyMap()): String</ID>
+    <ID>ThrowsCount:CryptoPrice.kt$CryptoPrice.Companion$ @JvmStatic @JvmOverloads @Throws(CryptoException::class, IOException::class) fun apiCall(paths: List&lt;String>, params: Map&lt;String, String> = emptyMap()): String</ID>
+    <ID>ThrowsCount:CryptoPrice.kt$CryptoPrice.Companion$@JvmStatic @Throws(CryptoException::class) fun String.toPrice(): CryptoPrice</ID>
   </CurrentIssues>
 </SmellBaseline>

examples/src/main/java/com/example/CryptoPriceSample.java

@@ -3,6 +3,7 @@ package com.example;
 import net.thauvin.erik.crypto.CryptoPrice;
 import net.thauvin.erik.crypto.CryptoException;
 
+import java.io.IOException;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
@@ -35,7 +36,7 @@ public class CryptoPriceSample {
             final CryptoPrice gbpPrice = CryptoPrice.marketPrice("ETH", "GBP");
             System.out.println("The current Ethereum price is " + gbpPrice.getAmount() + " in Pound sterling");
 
-        } catch (CryptoException e) {
+        } catch (CryptoException | IOException e) {
             System.err.println(e.getMessage());
         }
     }

src/main/kotlin/net/thauvin/erik/crypto/CryptoPrice.kt

@@ -35,7 +35,9 @@ package net.thauvin.erik.crypto
 import okhttp3.HttpUrl.Companion.toHttpUrl
 import okhttp3.OkHttpClient
 import okhttp3.Request
+import org.json.JSONException
 import org.json.JSONObject
+import java.io.IOException
 import java.time.LocalDate
 
 /**
@@ -49,6 +51,7 @@ open class CryptoPrice(val base: String, val currency: String, val amount: Doubl
         @JvmStatic
         @Throws(CryptoException::class)
         fun String.toPrice(): CryptoPrice {
+            try {
                 val json = JSONObject(this)
                 if (json.has("data")) {
                     with(json.getJSONObject("data")) {
@@ -57,7 +60,12 @@ open class CryptoPrice(val base: String, val currency: String, val amount: Doubl
                         )
                     }
                 } else {
-                throw CryptoException(message = "Missing JSON data.")
+                    throw CryptoException(message = "Missing price data.")
+                }
+            } catch (e: NumberFormatException) {
+                throw CryptoException(message = "Could not convert price data to number.", cause = e)
+            } catch (e: JSONException) {
+                throw CryptoException(message = "Could not parse price data.", cause = e)
             }
         }
 
@@ -66,10 +74,11 @@ open class CryptoPrice(val base: String, val currency: String, val amount: Doubl
          */
         @JvmStatic
         @JvmOverloads
-        @Throws(CryptoException::class)
+        @Throws(CryptoException::class, IOException::class)
         fun apiCall(paths: List<String>, params: Map<String, String> = emptyMap()): String {
             val client = OkHttpClient()
             val url = COINBASE_API_URL.toHttpUrl().newBuilder()
+
             paths.forEach {
                 url.addPathSegment(it)
             }
@@ -81,19 +90,19 @@ open class CryptoPrice(val base: String, val currency: String, val amount: Doubl
             val response = client.newCall(request).execute()
             val body = response.body?.string()
             if (body != null) {
+                try {
                     val json = JSONObject(body)
-                if (!response.isSuccessful) {
+                    if (response.isSuccessful) {
-                    if (json.has("errors")) {
+                        return body
+                    } else {
                         val data = json.getJSONArray("errors")
                         throw CryptoException(response.code, data.getJSONObject(0).getString("message"))
-                    } else {
+                    }
-                        throw CryptoException(response.code, "Invalid API response.")
+                } catch (e: JSONException) {
+                    throw CryptoException(response.code, "Could not parse data.", e)
                 }
             } else {
-                    return body
+                throw CryptoException(response.code, "Empty response.")
-                }
-            } else {
-                throw CryptoException(response.code, "Empty API response.")
             }
         }
 
@@ -104,11 +113,11 @@ open class CryptoPrice(val base: String, val currency: String, val amount: Doubl
         }
 
         /**
-         * Retrieves the current market price.
+         * Retrieve the current market price.
          */
         @JvmStatic
         @JvmOverloads
-        @Throws(CryptoException::class)
+        @Throws(CryptoException::class, IOException::class)
         fun marketPrice(base: String, currency: String = "USD", date: LocalDate? = null): CryptoPrice {
             val params = if (date != null) mapOf("date" to "$date") else emptyMap()
             val body = apiCall(listOf("prices", "$base-$currency", "spot"), params)

src/test/kotlin/net/thauvin/erik/crypto/CryptoPriceTest.kt

@@ -74,9 +74,16 @@ class CryptoPriceTest {
     @Throws(CryptoException::class)
     fun testToPrice() {
         val d = 57515.69
-        val price = "{\"data\":{\"base\":\"BTC\",\"currency\":\"USD\",\"amount\":\"$d\"}}".toPrice()
+        val json = "{\"data\":{\"base\":\"BTC\",\"currency\":\"USD\",\"amount\":\"$d\"}}"
+        val price = json.toPrice()
         assertEquals(price.base, "BTC", "base is BTC")
         assertEquals(price.currency, "USD", "currency is USD")
         assertEquals(price.amount, d, "amount is 57515.69")
+
+        assertFailsWith(
+            message = "double convertion did not fail",
+            exceptionClass = CryptoException::class,
+            block = { json.replace("5", "a").toPrice() }
+        )
     }
 }