8342865: Use type parameter for Class::getPrimitiveClass

Reviewed-by: darcy

Author: liach

src/java.base/share/classes/java/lang/Boolean.java

@@ -78,8 +78,7 @@ public final class Boolean implements java.io.Serializable,
      *
      * @since   1.1
      */
-    @SuppressWarnings("unchecked")
-    public static final Class<Boolean> TYPE = (Class<Boolean>) Class.getPrimitiveClass("boolean");
+    public static final Class<Boolean> TYPE = Class.getPrimitiveClass("boolean");
 
     /**
      * The value of the Boolean.

src/java.base/share/classes/java/lang/Byte.java

@@ -79,8 +79,7 @@ public final class Byte extends Number implements Comparable<Byte>, Constable {
      * The {@code Class} instance representing the primitive type
      * {@code byte}.
      */
-    @SuppressWarnings("unchecked")
-    public static final Class<Byte>     TYPE = (Class<Byte>) Class.getPrimitiveClass("byte");
+    public static final Class<Byte> TYPE = Class.getPrimitiveClass("byte");
 
     /**
      * Returns a new {@code String} object representing the

src/java.base/share/classes/java/lang/Character.java

@@ -232,8 +232,7 @@ class Character implements java.io.Serializable, Comparable<Character>, Constabl
      *
      * @since   1.1
      */
-    @SuppressWarnings("unchecked")
-    public static final Class<Character> TYPE = (Class<Character>) Class.getPrimitiveClass("char");
+    public static final Class<Character> TYPE = Class.getPrimitiveClass("char");
 
     /*
      * Normative general types

src/java.base/share/classes/java/lang/Class.java

@@ -3278,10 +3278,10 @@ ProtectionDomain protectionDomain() {
     private native ProtectionDomain getProtectionDomain0();
 
     /*
-     * Return the Virtual Machine's Class object for the named
-     * primitive type.
+     * Returns the Class object for the named primitive type. Type parameter T
+     * avoids redundant casts for trusted code.
      */
-    static native Class<?> getPrimitiveClass(String name);
+    static native <T> Class<T> getPrimitiveClass(String name);
 
     /*
      * Check if client is allowed to access members.  If access is denied,

src/java.base/share/classes/java/lang/Double.java

@@ -459,8 +459,7 @@ public final class Double extends Number
      *
      * @since 1.1
      */
-    @SuppressWarnings("unchecked")
-    public static final Class<Double>   TYPE = (Class<Double>) Class.getPrimitiveClass("double");
+    public static final Class<Double> TYPE = Class.getPrimitiveClass("double");
 
     /**
      * Returns a string representation of the {@code double}

src/java.base/share/classes/java/lang/Float.java

@@ -175,8 +175,7 @@ public final class Float extends Number
      *
      * @since 1.1
      */
-    @SuppressWarnings("unchecked")
-    public static final Class<Float> TYPE = (Class<Float>) Class.getPrimitiveClass("float");
+    public static final Class<Float> TYPE = Class.getPrimitiveClass("float");
 
     /**
      * Returns a string representation of the {@code float}

src/java.base/share/classes/java/lang/Integer.java

@@ -95,8 +95,7 @@ public final class Integer extends Number
      *
      * @since   1.1
      */
-    @SuppressWarnings("unchecked")
-    public static final Class<Integer>  TYPE = (Class<Integer>) Class.getPrimitiveClass("int");
+    public static final Class<Integer> TYPE = Class.getPrimitiveClass("int");
 
     /**
      * All possible chars for representing a number as a String

src/java.base/share/classes/java/lang/Long.java

@@ -95,8 +95,7 @@ public final class Long extends Number
      *
      * @since   1.1
      */
-    @SuppressWarnings("unchecked")
-    public static final Class<Long>     TYPE = (Class<Long>) Class.getPrimitiveClass("long");
+    public static final Class<Long> TYPE = Class.getPrimitiveClass("long");
 
     /**
      * Returns a string representation of the first argument in the

src/java.base/share/classes/java/lang/Short.java

@@ -79,8 +79,7 @@ public final class Short extends Number implements Comparable<Short>, Constable
      * The {@code Class} instance representing the primitive type
      * {@code short}.
      */
-    @SuppressWarnings("unchecked")
-    public static final Class<Short>    TYPE = (Class<Short>) Class.getPrimitiveClass("short");
+    public static final Class<Short> TYPE = Class.getPrimitiveClass("short");
 
     /**
      * Returns a new {@code String} object representing the

src/java.base/share/classes/java/lang/Void.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1996, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1996, 2024, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -39,8 +39,7 @@ class Void {
      * The {@code Class} object representing the pseudo-type corresponding to
      * the keyword {@code void}.
      */
-    @SuppressWarnings("unchecked")
-    public static final Class<Void> TYPE = (Class<Void>) Class.getPrimitiveClass("void");
+    public static final Class<Void> TYPE = Class.getPrimitiveClass("void");
 
     /*
      * The Void class cannot be instantiated.