src/java.base/share/classes/java/io/ObjectStreamField.java

rev 17455 : 8184603: Create ObjectStreamField signature lazily when possible
Reviewed-by: rriggs

*** 44,54 ****
  {
  
      /** field name */
      private final String name;
      /** canonical JVM signature of field type */
!     private final String signature;
      /** field type (Object.class if unknown non-primitive type) */
      private final Class<?> type;
      /** whether or not to (de)serialize field values as unshared */
      private final boolean unshared;
      /** corresponding reflective field object, if any */
--- 44,54 ----
  {
  
      /** field name */
      private final String name;
      /** canonical JVM signature of field type */
!     private volatile String signature;
      /** field type (Object.class if unknown non-primitive type) */
      private final Class<?> type;
      /** whether or not to (de)serialize field values as unshared */
      private final boolean unshared;
      /** corresponding reflective field object, if any */
*** 89,99 ****
              throw new NullPointerException();
          }
          this.name = name;
          this.type = type;
          this.unshared = unshared;
!         signature = getClassSignature(type).intern();
          field = null;
      }
  
      /**
       * Creates an ObjectStreamField representing a field with the given name,
--- 89,99 ----
              throw new NullPointerException();
          }
          this.name = name;
          this.type = type;
          this.unshared = unshared;
!         signature = null;
          field = null;
      }
  
      /**
       * Creates an ObjectStreamField representing a field with the given name,
*** 240,260 ****
       *
       * @return  the typecode of the serializable field
       */
      // REMIND: deprecate?
      public char getTypeCode() {
!         return signature.charAt(0);
      }
  
      /**
       * Return the JVM type signature.
       *
       * @return  null if this field has a primitive type.
       */
      // REMIND: deprecate?
      public String getTypeString() {
!         return isPrimitive() ? null : signature;
      }
  
      /**
       * Offset of field within instance data.
       *
--- 240,260 ----
       *
       * @return  the typecode of the serializable field
       */
      // REMIND: deprecate?
      public char getTypeCode() {
!         return getSignature().charAt(0);
      }
  
      /**
       * Return the JVM type signature.
       *
       * @return  null if this field has a primitive type.
       */
      // REMIND: deprecate?
      public String getTypeString() {
!         return isPrimitive() ? null : getSignature();
      }
  
      /**
       * Offset of field within instance data.
       *
*** 282,292 ****
       *
       * @return  true if and only if this field corresponds to a primitive type
       */
      // REMIND: deprecate?
      public boolean isPrimitive() {
!         char tcode = signature.charAt(0);
          return ((tcode != 'L') && (tcode != '['));
      }
  
      /**
       * Returns boolean value indicating whether or not the serializable field
--- 282,292 ----
       *
       * @return  true if and only if this field corresponds to a primitive type
       */
      // REMIND: deprecate?
      public boolean isPrimitive() {
!         char tcode = getTypeCode();
          return ((tcode != 'L') && (tcode != '['));
      }
  
      /**
       * Returns boolean value indicating whether or not the serializable field
*** 334,341 ****
      /**
       * Returns JVM type signature of field (similar to getTypeString, except
       * that signature strings are returned for primitive fields as well).
       */
      String getSignature() {
!         return signature;
      }
  }
--- 334,349 ----
      /**
       * Returns JVM type signature of field (similar to getTypeString, except
       * that signature strings are returned for primitive fields as well).
       */
      String getSignature() {
!         String sig = signature;
! 
!         // This lazy calculation is safe since sig can be null iff one of the
!         // public constructors are used, in which case type is always
!         // initialized to the exact type we want the signature to represent.
!         if (sig == null) {
!             sig = signature = getClassSignature(type).intern();
!         }
!         return sig;
      }
  }