From 399c52430031ad171c9f1dda5d905a88f449c616 Mon Sep 17 00:00:00 2001
From: Marcono1234 <Marcono1234@users.noreply.github.com>
Date: Sat, 6 Aug 2022 15:13:56 +0200
Subject: [PATCH 1/2] Fix TypeAdapter.toJson throwing AssertionError for custom
 IOException

---
 .../java/com/google/gson/TypeAdapter.java     |  2 +-
 .../java/com/google/gson/TypeAdapterTest.java | 33 +++++++++++++++++++
 2 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/gson/src/main/java/com/google/gson/TypeAdapter.java b/gson/src/main/java/com/google/gson/TypeAdapter.java
index ba798537be..72a3b1a21d 100644
--- a/gson/src/main/java/com/google/gson/TypeAdapter.java
+++ b/gson/src/main/java/com/google/gson/TypeAdapter.java
@@ -216,7 +216,7 @@ public final String toJson(T value) {
     try {
       toJson(stringWriter, value);
     } catch (IOException e) {
-      throw new AssertionError(e); // No I/O writing to a StringWriter.
+      throw new JsonIOException(e);
     }
     return stringWriter.toString();
   }
diff --git a/gson/src/test/java/com/google/gson/TypeAdapterTest.java b/gson/src/test/java/com/google/gson/TypeAdapterTest.java
index ab44637393..725ecdae93 100644
--- a/gson/src/test/java/com/google/gson/TypeAdapterTest.java
+++ b/gson/src/test/java/com/google/gson/TypeAdapterTest.java
@@ -2,6 +2,7 @@
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNull;
+import static org.junit.Assert.fail;
 
 import com.google.gson.stream.JsonReader;
 import com.google.gson.stream.JsonWriter;
@@ -26,6 +27,38 @@ public void testNullSafe() throws IOException {
     assertNull(adapter.fromJson("null"));
   }
 
+  /**
+   * Tests behavior when {@link TypeAdapter#write(JsonWriter, Object)} manually throws
+   * {@link IOException} which is not caused by writer usage.
+   */
+  @Test
+  public void testToJson_ThrowingIOException() {
+    final IOException exception = new IOException("test");
+    TypeAdapter<Integer> adapter = new TypeAdapter<Integer>() {
+      @Override public void write(JsonWriter out, Integer value) throws IOException {
+        throw exception;
+      }
+
+      @Override public Integer read(JsonReader in) throws IOException {
+        throw new AssertionError("not needed by this test");
+      }
+    };
+
+    try {
+      adapter.toJson(1);
+      fail();
+    } catch (JsonIOException e) {
+      assertEquals(exception, e.getCause());
+    }
+
+    try {
+      adapter.toJsonTree(1);
+      fail();
+    } catch (JsonIOException e) {
+      assertEquals(exception, e.getCause());
+    }
+  }
+
   private static final TypeAdapter<String> adapter = new TypeAdapter<String>() {
     @Override public void write(JsonWriter out, String value) throws IOException {
       out.value(value);

From c42703d651e20095c64d4717cd859fae3a9a17e1 Mon Sep 17 00:00:00 2001
From: Marcono1234 <Marcono1234@users.noreply.github.com>
Date: Mon, 8 Aug 2022 01:37:10 +0200
Subject: [PATCH 2/2] Add throws javadoc tag for TypeAdapter methods

---
 gson/src/main/java/com/google/gson/TypeAdapter.java | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/gson/src/main/java/com/google/gson/TypeAdapter.java b/gson/src/main/java/com/google/gson/TypeAdapter.java
index 72a3b1a21d..37f22b8e22 100644
--- a/gson/src/main/java/com/google/gson/TypeAdapter.java
+++ b/gson/src/main/java/com/google/gson/TypeAdapter.java
@@ -131,8 +131,7 @@ public abstract class TypeAdapter<T> {
    * Unlike Gson's similar {@link Gson#toJson(JsonElement, Appendable) toJson}
    * method, this write is strict. Create a {@link
    * JsonWriter#setLenient(boolean) lenient} {@code JsonWriter} and call
-   * {@link #write(com.google.gson.stream.JsonWriter, Object)} for lenient
-   * writing.
+   * {@link #write(JsonWriter, Object)} for lenient writing.
    *
    * @param value the Java object to convert. May be null.
    * @since 2.2
@@ -205,9 +204,9 @@ public final TypeAdapter<T> nullSafe() {
    * Converts {@code value} to a JSON document. Unlike Gson's similar {@link
    * Gson#toJson(Object) toJson} method, this write is strict. Create a {@link
    * JsonWriter#setLenient(boolean) lenient} {@code JsonWriter} and call
-   * {@link #write(com.google.gson.stream.JsonWriter, Object)} for lenient
-   * writing.
+   * {@link #write(JsonWriter, Object)} for lenient writing.
    *
+   * @throws JsonIOException wrapping {@code IOException}s thrown by {@link #write(JsonWriter, Object)}
    * @param value the Java object to convert. May be null.
    * @since 2.2
    */
@@ -226,6 +225,7 @@ public final String toJson(T value) {
    *
    * @param value the Java object to convert. May be null.
    * @return the converted JSON tree. May be {@link JsonNull}.
+   * @throws JsonIOException wrapping {@code IOException}s thrown by {@link #write(JsonWriter, Object)}
    * @since 2.2
    */
   public final JsonElement toJsonTree(T value) {
@@ -248,7 +248,7 @@ public final JsonElement toJsonTree(T value) {
 
   /**
    * Converts the JSON document in {@code in} to a Java object. Unlike Gson's
-   * similar {@link Gson#fromJson(java.io.Reader, Class) fromJson} method, this
+   * similar {@link Gson#fromJson(Reader, Class) fromJson} method, this
    * read is strict. Create a {@link JsonReader#setLenient(boolean) lenient}
    * {@code JsonReader} and call {@link #read(JsonReader)} for lenient reading.
    *
@@ -284,6 +284,7 @@ public final T fromJson(String json) throws IOException {
    *
    * @param jsonTree the JSON element to convert. May be {@link JsonNull}.
    * @return the converted Java object. May be null.
+   * @throws JsonIOException wrapping {@code IOException}s thrown by {@link #read(JsonReader)}
    * @since 2.2
    */
   public final T fromJsonTree(JsonElement jsonTree) {