Use pattern matching instead of type casting.

Closes spring-projects#2754

Author: junghoon-vans

src/main/java/org/springframework/data/redis/connection/DefaultStringRedisConnection.java

@@ -23,7 +23,6 @@
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-
 import org.springframework.core.convert.converter.Converter;
 import org.springframework.data.geo.Circle;
 import org.springframework.data.geo.Distance;
@@ -35,19 +34,10 @@
 import org.springframework.data.redis.connection.convert.ListConverter;
 import org.springframework.data.redis.connection.convert.MapConverter;
 import org.springframework.data.redis.connection.convert.SetConverter;
-import org.springframework.data.redis.connection.stream.ByteRecord;
-import org.springframework.data.redis.connection.stream.Consumer;
-import org.springframework.data.redis.connection.stream.MapRecord;
-import org.springframework.data.redis.connection.stream.PendingMessages;
-import org.springframework.data.redis.connection.stream.PendingMessagesSummary;
-import org.springframework.data.redis.connection.stream.ReadOffset;
-import org.springframework.data.redis.connection.stream.RecordId;
+import org.springframework.data.redis.connection.stream.*;
 import org.springframework.data.redis.connection.stream.StreamInfo.XInfoConsumers;
 import org.springframework.data.redis.connection.stream.StreamInfo.XInfoGroups;
 import org.springframework.data.redis.connection.stream.StreamInfo.XInfoStream;
-import org.springframework.data.redis.connection.stream.StreamOffset;
-import org.springframework.data.redis.connection.stream.StreamReadOptions;
-import org.springframework.data.redis.connection.stream.StringRecord;
 import org.springframework.data.redis.connection.zset.Aggregate;
 import org.springframework.data.redis.connection.zset.DefaultTuple;
 import org.springframework.data.redis.connection.zset.Tuple;
@@ -3046,8 +3036,8 @@ private <T> T convertAndReturn(@Nullable Object value, Converter converter) {
 return null;
 }
 
-if (!(converter instanceof ListConverter) && value instanceof List) {
-return (T) new ListConverter<>(converter).convert((List) value);
+if (!(converter instanceof ListConverter) && value instanceof List list) {
+return (T) new ListConverter<>(converter).convert(list);
 }
 
 return value == null ? null

src/main/java/org/springframework/data/redis/connection/RedisNode.java

@@ -274,12 +274,10 @@ public boolean equals(@Nullable Object obj) {
 if (this == obj) {
 return true;
 }
-if (obj == null || !(obj instanceof RedisNode)) {
+if (obj == null || !(obj instanceof RedisNode other)) {
 return false;
 }
 
-RedisNode other = (RedisNode) obj;
-
 if (!ObjectUtils.nullSafeEquals(this.host, other.host)) {
 return false;
 }

src/main/java/org/springframework/data/redis/connection/convert/Converters.java

@@ -421,17 +421,16 @@ public static Object parse(Object source, String sourcePath, Map<String, Class<?
 if (source instanceof String) {
 return source.toString();
 }
-if (source instanceof byte[]) {
-return new String((byte[]) source);
+if (source instanceof byte[] bytes) {
+return new String(bytes);
 }
-if (source instanceof ByteBuffer) {
-return new String(ByteUtils.getBytes((ByteBuffer) source));
+if (source instanceof ByteBuffer byteBuffer) {
+return new String(ByteUtils.getBytes(byteBuffer));
 }
 }
 
-if (ClassUtils.isAssignable(List.class, targetType) && source instanceof List) {
+if (ClassUtils.isAssignable(List.class, targetType) && source instanceof List<?> sourceCollection) {
 
-List<Object> sourceCollection = (List<Object>) source;
 List<Object> targetList = new ArrayList<>();
 
 for (int i = 0; i < sourceCollection.size(); i++) {
@@ -441,9 +440,8 @@ public static Object parse(Object source, String sourcePath, Map<String, Class<?
 return targetList;
 }
 
-if (ClassUtils.isAssignable(Map.class, targetType) && source instanceof List) {
+if (ClassUtils.isAssignable(Map.class, targetType) && source instanceof List<?> sourceCollection) {
 
-List<Object> sourceCollection = ((List<Object>) source);
 Map<String, Object> targetMap = new LinkedHashMap<>();
 
 for (int i = 0; i < sourceCollection.size(); i = i + 2) {

src/main/java/org/springframework/data/redis/connection/convert/TransactionResultConverter.java

@@ -58,9 +58,8 @@ public List<Object> convert(List<Object> execResults) {
 
 for (Object result : execResults) {
 FutureResult<T> futureResult = txResults.remove();
-if (result instanceof Exception) {
+if (result instanceof Exception source) {
 
-Exception source = (Exception) result;
 DataAccessException convertedException = exceptionConverter.convert(source);
 throw convertedException != null ? convertedException
 : new RedisSystemException("Error reading future result", source);

src/main/java/org/springframework/data/redis/connection/jedis/JedisConverters.java

@@ -88,8 +88,6 @@
 import org.springframework.util.ObjectUtils;
 import org.springframework.util.StringUtils;
 
-import redis.clients.jedis.util.SafeEncoder;
-
 /**
  * Jedis type converters.
  *
@@ -470,16 +468,16 @@ private static byte[] boundaryToBytes(org.springframework.data.domain.Range.Boun
 byte[] prefix = boundary.isInclusive() ? inclPrefix : exclPrefix;
 byte[] value = null;
 Object theValue = boundary.getValue().get();
-if (theValue instanceof byte[]) {
-value = (byte[]) theValue;
-} else if (theValue instanceof Double) {
-value = toBytes((Double) theValue);
-} else if (theValue instanceof Long) {
-value = toBytes((Long) theValue);
-} else if (theValue instanceof Integer) {
-value = toBytes((Integer) theValue);
-} else if (theValue instanceof String) {
-value = toBytes((String) theValue);
+if (theValue instanceof byte[] bytes) {
+value = bytes;
+} else if (theValue instanceof Double doubleValue) {
+value = toBytes(doubleValue);
+} else if (theValue instanceof Long longValue) {
+value = toBytes(longValue);
+} else if (theValue instanceof Integer integer) {
+value = toBytes(integer);
+} else if (theValue instanceof String string) {
+value = toBytes(string);
 } else {
 throw new IllegalArgumentException(String.format("Cannot convert %s to binary format", boundary.getValue()));
 }

src/main/java/org/springframework/data/redis/connection/jedis/JedisExceptionConverter.java

@@ -45,8 +45,8 @@ public class JedisExceptionConverter implements Converter<Exception, DataAccessE
 
 public DataAccessException convert(Exception ex) {
 
-if (ex instanceof DataAccessException) {
-return (DataAccessException) ex;
+if (ex instanceof DataAccessException dataAccessException) {
+return dataAccessException;
 }
 
 if (ex instanceof UnsupportedOperationException) {
@@ -57,10 +57,10 @@ public DataAccessException convert(Exception ex) {
 return new TooManyClusterRedirectionsException(ex.getMessage(), ex);
 }
 
-if (ex instanceof JedisRedirectionException) {
+if (ex instanceof JedisRedirectionException redirectionException) {
 
-JedisRedirectionException re = (JedisRedirectionException) ex;
-return new ClusterRedirectException(re.getSlot(), re.getTargetNode().getHost(), re.getTargetNode().getPort(), ex);
+return new ClusterRedirectException(redirectionException.getSlot(),
+redirectionException.getTargetNode().getHost(), redirectionException.getTargetNode().getPort(), ex);
 }
 
 if (ex instanceof JedisConnectionException) {

src/main/java/org/springframework/data/redis/connection/jedis/JedisScriptReturnConverter.java

@@ -39,9 +39,9 @@ public JedisScriptReturnConverter(ReturnType returnType) {
 
 @SuppressWarnings("unchecked")
 public Object convert(@Nullable Object result) {
-if (result instanceof String) {
+if (result instanceof String stringResult) {
 // evalsha converts byte[] to String. Convert back for consistency
-return SafeEncoder.encode((String) result);
+return SafeEncoder.encode(stringResult);
 }
 if (returnType == ReturnType.STATUS) {
 return JedisConverters.toString((byte[]) result);
@@ -57,10 +57,10 @@ public Object convert(@Nullable Object result) {
 List<Object> resultList = (List<Object>) result;
 List<Object> convertedResults = new ArrayList<>();
 for (Object res : resultList) {
-if (res instanceof String) {
+if (res instanceof String stringResult) {
 // evalsha converts byte[] to String. Convert back for
 // consistency
-convertedResults.add(SafeEncoder.encode((String) res));
+convertedResults.add(SafeEncoder.encode(stringResult));
 } else {
 convertedResults.add(res);
 }

src/main/java/org/springframework/data/redis/connection/lettuce/LettuceExceptionConverter.java

@@ -46,14 +46,14 @@ public DataAccessException convert(Exception ex) {
 
 if (ex instanceof ExecutionException || ex instanceof RedisCommandExecutionException) {
 
-if (ex.getCause() != ex && ex.getCause() instanceof Exception) {
-return convert((Exception) ex.getCause());
+if (ex.getCause() != ex && ex.getCause() instanceof Exception cause) {
+return convert(cause);
 }
 return new RedisSystemException("Error in execution", ex);
 }
 
-if (ex instanceof DataAccessException) {
-return (DataAccessException) ex;
+if (ex instanceof DataAccessException dataAccessException) {
+return dataAccessException;
 }
 
 if (ex instanceof RedisCommandInterruptedException) {

src/main/java/org/springframework/data/redis/connection/lettuce/LettuceScriptingCommands.java

@@ -134,8 +134,8 @@ public T convert(Object source) {
 if (returnType == ReturnType.MULTI) {
 List resultList = (List) source;
 for (Object obj : resultList) {
-if (obj instanceof Exception) {
-throw connection.convertLettuceAccessException((Exception) obj);
+if (obj instanceof Exception ex) {
+throw connection.convertLettuceAccessException(ex);
 }
 }
 }

src/main/java/org/springframework/data/redis/connection/lettuce/LettuceSubscription.java

@@ -60,7 +60,7 @@ protected LettuceSubscription(MessageListener listener,
 
 this.connection = pubsubConnection;
 this.listener = new LettuceMessageListener(listener,
-listener instanceof SubscriptionListener ? (SubscriptionListener) listener
+listener instanceof SubscriptionListener subscriptionListener ? subscriptionListener
 : SubscriptionListener.NO_OP_SUBSCRIPTION_LISTENER);
 this.connectionProvider = connectionProvider;
 this.pubsub = connection.sync();