AJ-423、AJ-424: optimize some code logic; update junit from 4.12 to 4.13.2;

Author: chengyitian

pom.xml

@@ -37,7 +37,7 @@
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>
-            <version>4.12</version>
+            <version>4.13.2</version>
             <scope>test</scope>
         </dependency>
         <dependency>

src/com/xxdb/data/BasicDecimal32.java

@@ -3,7 +3,6 @@
 import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.xxdb.io.ExtendedDataInput;
 import com.xxdb.io.ExtendedDataOutput;
-
 import java.io.IOException;
 import java.math.BigDecimal;
 import java.time.temporal.Temporal;