Make dependency on java.sql optional

gson/src/main/java/com/google/gson/Gson.java

@@ -49,9 +49,8 @@
 import com.google.gson.internal.bind.MapTypeAdapterFactory;
 import com.google.gson.internal.bind.ObjectTypeAdapter;
 import com.google.gson.internal.bind.ReflectiveTypeAdapterFactory;
-import com.google.gson.internal.bind.SqlDateTypeAdapter;
-import com.google.gson.internal.bind.TimeTypeAdapter;
 import com.google.gson.internal.bind.TypeAdapters;
+import com.google.gson.internal.sql.SqlTypesSupport;
 import com.google.gson.reflect.TypeToken;
 import com.google.gson.stream.JsonReader;
 import com.google.gson.stream.JsonToken;
@@ -262,9 +261,13 @@ public Gson() {
     factories.add(TypeAdapters.BIT_SET_FACTORY);
     factories.add(DateTypeAdapter.FACTORY);
     factories.add(TypeAdapters.CALENDAR_FACTORY);
-    factories.add(TimeTypeAdapter.FACTORY);
-    factories.add(SqlDateTypeAdapter.FACTORY);
-    factories.add(TypeAdapters.TIMESTAMP_FACTORY);
+
+    if (SqlTypesSupport.SUPPORTS_SQL_TYPES) {
+      factories.add(SqlTypesSupport.TIME_FACTORY);
+      factories.add(SqlTypesSupport.DATE_FACTORY);
+      factories.add(SqlTypesSupport.TIMESTAMP_FACTORY);
+    }
+
     factories.add(ArrayTypeAdapter.FACTORY);
     factories.add(TypeAdapters.CLASS_FACTORY);
 

gson/src/main/java/com/google/gson/GsonBuilder.java

@@ -17,7 +17,6 @@
 package com.google.gson;
 
 import java.lang.reflect.Type;
-import java.sql.Timestamp;
 import java.text.DateFormat;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -28,8 +27,10 @@
 
 import com.google.gson.internal.$Gson$Preconditions;
 import com.google.gson.internal.Excluder;
+import com.google.gson.internal.bind.DefaultDateTypeAdapter;
 import com.google.gson.internal.bind.TreeTypeAdapter;
 import com.google.gson.internal.bind.TypeAdapters;
+import com.google.gson.internal.sql.SqlTypesSupport;
 import com.google.gson.reflect.TypeToken;
 import com.google.gson.stream.JsonReader;
 
@@ -417,8 +418,8 @@ public GsonBuilder disableHtmlEscaping() {
    * call this method or {@link #setDateFormat(int)} multiple times, but only the last invocation
    * will be used to decide the serialization format.
    *
-   * <p>The date format will be used to serialize and deserialize {@link java.util.Date}, {@link
-   * java.sql.Timestamp} and {@link java.sql.Date}.
+   * <p>The date format will be used to serialize and deserialize {@link java.util.Date} and in case
+   * the {@code java.sql} module is present, also {@link java.sql.Timestamp} and {@link java.sql.Date}.
    *
    * <p>Note that this pattern must abide by the convention provided by {@code SimpleDateFormat}
    * class. See the documentation in {@link java.text.SimpleDateFormat} for more information on
@@ -602,26 +603,35 @@ public Gson create() {
         this.factories, this.hierarchyFactories, factories);
   }
 
-  @SuppressWarnings("unchecked")
   private void addTypeAdaptersForDate(String datePattern, int dateStyle, int timeStyle,
       List<TypeAdapterFactory> factories) {
-    DefaultDateTypeAdapter dateTypeAdapter;
-    TypeAdapter<Timestamp> timestampTypeAdapter;
-    TypeAdapter<java.sql.Date> javaSqlDateTypeAdapter;
-    if (datePattern != null && !"".equals(datePattern.trim())) {
-      dateTypeAdapter = new DefaultDateTypeAdapter(Date.class, datePattern);
-      timestampTypeAdapter = (TypeAdapter) new DefaultDateTypeAdapter(Timestamp.class, datePattern);
-      javaSqlDateTypeAdapter = (TypeAdapter) new DefaultDateTypeAdapter(java.sql.Date.class, datePattern);
+    TypeAdapterFactory dateAdapterFactory;
+    boolean sqlTypesSupported = SqlTypesSupport.SUPPORTS_SQL_TYPES;
+    TypeAdapterFactory sqlTimestampAdapterFactory = null;
+    TypeAdapterFactory sqlDateAdapterFactory = null;
+
+    if (datePattern != null && !datePattern.trim().isEmpty()) {
+      dateAdapterFactory = DefaultDateTypeAdapter.DateType.DATE.createAdapterFactory(datePattern);
+
+      if (sqlTypesSupported) {
+        sqlTimestampAdapterFactory = SqlTypesSupport.TIMESTAMP_DATE_TYPE.createAdapterFactory(datePattern);
+        sqlDateAdapterFactory = SqlTypesSupport.DATE_DATE_TYPE.createAdapterFactory(datePattern);
+      }
     } else if (dateStyle != DateFormat.DEFAULT && timeStyle != DateFormat.DEFAULT) {
-      dateTypeAdapter = new DefaultDateTypeAdapter(Date.class, dateStyle, timeStyle);
-      timestampTypeAdapter = (TypeAdapter) new DefaultDateTypeAdapter(Timestamp.class, dateStyle, timeStyle);
-      javaSqlDateTypeAdapter = (TypeAdapter) new DefaultDateTypeAdapter(java.sql.Date.class, dateStyle, timeStyle);
+      dateAdapterFactory = DefaultDateTypeAdapter.DateType.DATE.createAdapterFactory(dateStyle, timeStyle);
+
+      if (sqlTypesSupported) {
+        sqlTimestampAdapterFactory = SqlTypesSupport.TIMESTAMP_DATE_TYPE.createAdapterFactory(dateStyle, timeStyle);
+        sqlDateAdapterFactory = SqlTypesSupport.DATE_DATE_TYPE.createAdapterFactory(dateStyle, timeStyle);
+      }
     } else {
       return;
     }
 
-    factories.add(TypeAdapters.newFactory(Date.class, dateTypeAdapter));
-    factories.add(TypeAdapters.newFactory(Timestamp.class, timestampTypeAdapter));
-    factories.add(TypeAdapters.newFactory(java.sql.Date.class, javaSqlDateTypeAdapter));
+    factories.add(dateAdapterFactory);
+    if (sqlTypesSupported) {
+      factories.add(sqlTimestampAdapterFactory);
+      factories.add(sqlDateAdapterFactory);
+    }
   }
 }

gson/src/main/java/com/google/gson/internal/$Gson$Types.java

@@ -339,6 +339,7 @@ public static Type[] getMapKeyAndValueTypes(Type context, Class<?> contextRawTyp
   }
 
   public static Type resolve(Type context, Class<?> contextRawType, Type toResolve) {
+
     return resolve(context, contextRawType, toResolve, new HashMap<TypeVariable<?>, Type>());
   }
 

gson/src/main/java/com/google/gson/DefaultDateTypeAdapter.java → gson/src/main/java/com/google/gson/internal/bind/DefaultDateTypeAdapter.java

@@ -14,10 +14,9 @@
  * limitations under the License.
  */
 
-package com.google.gson;
+package com.google.gson.internal.bind;
 
 import java.io.IOException;
-import java.sql.Timestamp;
 import java.text.DateFormat;
 import java.text.ParseException;
 import java.text.ParsePosition;
@@ -27,6 +26,10 @@
 import java.util.List;
 import java.util.Locale;
 
+import com.google.gson.JsonSyntaxException;
+import com.google.gson.TypeAdapter;
+import com.google.gson.TypeAdapterFactory;
+import com.google.gson.internal.$Gson$Preconditions;
 import com.google.gson.internal.JavaVersion;
 import com.google.gson.internal.PreJava9DateFormatProvider;
 import com.google.gson.internal.bind.util.ISO8601Utils;
@@ -35,45 +38,70 @@
 import com.google.gson.stream.JsonWriter;
 
 /**
- * This type adapter supports three subclasses of date: Date, Timestamp, and
- * java.sql.Date.
+ * This type adapter supports subclasses of date by defining a
+ * {@link DefaultDateTypeAdapter.DateType} and then using its {@code createAdapterFactory}
+ * methods.
  *
  * @author Inderjeet Singh
  * @author Joel Leitch
  */
-final class DefaultDateTypeAdapter extends TypeAdapter<Date> {
-
+public final class DefaultDateTypeAdapter<T extends Date> extends TypeAdapter<T> {
   private static final String SIMPLE_NAME = "DefaultDateTypeAdapter";
 
-  private final Class<? extends Date> dateType;
+  public static abstract class DateType<T extends Date> {
+    public static final DateType<Date> DATE = new DateType<Date>(Date.class) {
+      @Override protected Date deserialize(Date date) {
+        return date;
+      }
+    };
+
+    private final Class<T> dateClass;
+
+    protected DateType(Class<T> dateClass) {
+      this.dateClass = dateClass;
+    }
+
+    protected abstract T deserialize(Date date);
+
+    private final TypeAdapterFactory createFactory(DefaultDateTypeAdapter<T> adapter) {
+      return TypeAdapters.newFactory(dateClass, adapter);
+    }
+
+    public final TypeAdapterFactory createAdapterFactory(String datePattern) {
+      return createFactory(new DefaultDateTypeAdapter<T>(this, datePattern));
+    }
+
+    public final TypeAdapterFactory createAdapterFactory(int style) {
+      return createFactory(new DefaultDateTypeAdapter<T>(this, style));
+    }
+
+    public final TypeAdapterFactory createAdapterFactory(int dateStyle, int timeStyle) {
+      return createFactory(new DefaultDateTypeAdapter<T>(this, dateStyle, timeStyle));
+    }
+
+    public final TypeAdapterFactory createDefaultsAdapterFactory() {
+      return createFactory(new DefaultDateTypeAdapter<T>(this, DateFormat.DEFAULT, DateFormat.DEFAULT));
+    }
+  }
+
+  private final DateType<T> dateType;
 
   /**
    * List of 1 or more different date formats used for de-serialization attempts.
    * The first of them is used for serialization as well.
    */
   private final List<DateFormat> dateFormats = new ArrayList<DateFormat>();
 
-  DefaultDateTypeAdapter(Class<? extends Date> dateType) {
-    this.dateType = verifyDateType(dateType);
-    dateFormats.add(DateFormat.getDateTimeInstance(DateFormat.DEFAULT, DateFormat.DEFAULT, Locale.US));
-    if (!Locale.getDefault().equals(Locale.US)) {
-      dateFormats.add(DateFormat.getDateTimeInstance(DateFormat.DEFAULT, DateFormat.DEFAULT));
-    }
-    if (JavaVersion.isJava9OrLater()) {
-      dateFormats.add(PreJava9DateFormatProvider.getUSDateTimeFormat(DateFormat.DEFAULT, DateFormat.DEFAULT));
-    }
-  }
-
-  DefaultDateTypeAdapter(Class<? extends Date> dateType, String datePattern) {
-    this.dateType = verifyDateType(dateType);
+  private DefaultDateTypeAdapter(DateType<T> dateType, String datePattern) {
+    this.dateType = $Gson$Preconditions.checkNotNull(dateType);
     dateFormats.add(new SimpleDateFormat(datePattern, Locale.US));
     if (!Locale.getDefault().equals(Locale.US)) {
       dateFormats.add(new SimpleDateFormat(datePattern));
     }
   }
 
-  DefaultDateTypeAdapter(Class<? extends Date> dateType, int style) {
-    this.dateType = verifyDateType(dateType);
+  private DefaultDateTypeAdapter(DateType<T> dateType, int style) {
+    this.dateType = $Gson$Preconditions.checkNotNull(dateType);
     dateFormats.add(DateFormat.getDateInstance(style, Locale.US));
     if (!Locale.getDefault().equals(Locale.US)) {
       dateFormats.add(DateFormat.getDateInstance(style));
@@ -83,12 +111,8 @@ final class DefaultDateTypeAdapter extends TypeAdapter<Date> {
     }
   }
 
-  public DefaultDateTypeAdapter(int dateStyle, int timeStyle) {
-    this(Date.class, dateStyle, timeStyle);
-  }
-
-  public DefaultDateTypeAdapter(Class<? extends Date> dateType, int dateStyle, int timeStyle) {
-    this.dateType = verifyDateType(dateType);
+  private DefaultDateTypeAdapter(DateType<T> dateType, int dateStyle, int timeStyle) {
+    this.dateType = $Gson$Preconditions.checkNotNull(dateType);
     dateFormats.add(DateFormat.getDateTimeInstance(dateStyle, timeStyle, Locale.US));
     if (!Locale.getDefault().equals(Locale.US)) {
       dateFormats.add(DateFormat.getDateTimeInstance(dateStyle, timeStyle));
@@ -98,13 +122,6 @@ public DefaultDateTypeAdapter(Class<? extends Date> dateType, int dateStyle, int
     }
   }
 
-  private static Class<? extends Date> verifyDateType(Class<? extends Date> dateType) {
-    if ( dateType != Date.class && dateType != java.sql.Date.class && dateType != Timestamp.class ) {
-      throw new IllegalArgumentException("Date type must be one of " + Date.class + ", " + Timestamp.class + ", or " + java.sql.Date.class + " but was " + dateType);
-    }
-    return dateType;
-  }
-
   // These methods need to be synchronized since JDK DateFormat classes are not thread-safe
   // See issue 162
   @Override
@@ -120,22 +137,13 @@ public void write(JsonWriter out, Date value) throws IOException {
   }
 
   @Override
-  public Date read(JsonReader in) throws IOException {
+  public T read(JsonReader in) throws IOException {
     if (in.peek() == JsonToken.NULL) {
       in.nextNull();
       return null;
     }
     Date date = deserializeToDate(in.nextString());
-    if (dateType == Date.class) {
-      return date;
-    } else if (dateType == Timestamp.class) {
-      return new Timestamp(date.getTime());
-    } else if (dateType == java.sql.Date.class) {
-      return new java.sql.Date(date.getTime());
-    } else {
-      // This must never happen: dateType is guarded in the primary constructor
-      throw new AssertionError();
-    }
+    return dateType.deserialize(date);
   }
 
   private Date deserializeToDate(String s) {
@@ -145,11 +153,12 @@ private Date deserializeToDate(String s) {
           return dateFormat.parse(s);
         } catch (ParseException ignored) {}
       }
-      try {
-        return ISO8601Utils.parse(s, new ParsePosition(0));
-      } catch (ParseException e) {
-        throw new JsonSyntaxException(s, e);
-      }
+    }
+
+    try {
+      return ISO8601Utils.parse(s, new ParsePosition(0));
+    } catch (ParseException e) {
+      throw new JsonSyntaxException(s, e);
     }
   }
 

gson/src/main/java/com/google/gson/internal/bind/TypeAdapters.java

@@ -26,12 +26,10 @@
 import java.net.URL;
 import java.security.AccessController;
 import java.security.PrivilegedAction;
-import java.sql.Timestamp;
 import java.util.ArrayList;
 import java.util.BitSet;
 import java.util.Calendar;
 import java.util.Currency;
-import java.util.Date;
 import java.util.GregorianCalendar;
 import java.util.HashMap;
 import java.util.List;
@@ -409,7 +407,7 @@ public void write(JsonWriter out, String value) throws IOException {
       out.value(value);
     }
   };
-  
+
   public static final TypeAdapter<BigDecimal> BIG_DECIMAL = new TypeAdapter<BigDecimal>() {
     @Override public BigDecimal read(JsonReader in) throws IOException {
       if (in.peek() == JsonToken.NULL) {
@@ -427,7 +425,7 @@ public void write(JsonWriter out, String value) throws IOException {
       out.value(value);
     }
   };
-  
+
   public static final TypeAdapter<BigInteger> BIG_INTEGER = new TypeAdapter<BigInteger>() {
     @Override public BigInteger read(JsonReader in) throws IOException {
       if (in.peek() == JsonToken.NULL) {
@@ -572,27 +570,6 @@ public void write(JsonWriter out, Currency value) throws IOException {
   }.nullSafe();
   public static final TypeAdapterFactory CURRENCY_FACTORY = newFactory(Currency.class, CURRENCY);
 
-  public static final TypeAdapterFactory TIMESTAMP_FACTORY = new TypeAdapterFactory() {
-    @SuppressWarnings("unchecked") // we use a runtime check to make sure the 'T's equal
-    @Override public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> typeToken) {
-      if (typeToken.getRawType() != Timestamp.class) {
-        return null;
-      }
-
-      final TypeAdapter<Date> dateTypeAdapter = gson.getAdapter(Date.class);
-      return (TypeAdapter<T>) new TypeAdapter<Timestamp>() {
-        @Override public Timestamp read(JsonReader in) throws IOException {
-          Date date = dateTypeAdapter.read(in);
-          return date != null ? new Timestamp(date.getTime()) : null;
-        }
-
-        @Override public void write(JsonWriter out, Timestamp value) throws IOException {
-          dateTypeAdapter.write(out, value);
-        }
-      };
-    }
-  };
-
   public static final TypeAdapter<Calendar> CALENDAR = new TypeAdapter<Calendar>() {
     private static final String YEAR = "year";
     private static final String MONTH = "month";

gson/src/main/java/com/google/gson/internal/bind/SqlDateTypeAdapter.java → gson/src/main/java/com/google/gson/internal/sql/SqlDateTypeAdapter.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package com.google.gson.internal.bind;
+package com.google.gson.internal.sql;
 
 import com.google.gson.Gson;
 import com.google.gson.JsonSyntaxException;
@@ -35,8 +35,8 @@
  * this class state. DateFormat isn't thread safe either, so this class has
  * to synchronize its read and write methods.
  */
-public final class SqlDateTypeAdapter extends TypeAdapter<java.sql.Date> {
-  public static final TypeAdapterFactory FACTORY = new TypeAdapterFactory() {
+final class SqlDateTypeAdapter extends TypeAdapter<java.sql.Date> {
+  static final TypeAdapterFactory FACTORY = new TypeAdapterFactory() {
     @SuppressWarnings("unchecked") // we use a runtime check to make sure the 'T's equal
     @Override public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> typeToken) {
       return typeToken.getRawType() == java.sql.Date.class
@@ -46,6 +46,9 @@ public final class SqlDateTypeAdapter extends TypeAdapter<java.sql.Date> {
 
   private final DateFormat format = new SimpleDateFormat("MMM d, yyyy");
 
+  private SqlDateTypeAdapter() {
+  }
+
   @Override
   public synchronized java.sql.Date read(JsonReader in) throws IOException {
     if (in.peek() == JsonToken.NULL) {