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record Point( int x, int y) { } data class Point( val x: Int, val y: Int) 

data class Point( val x: Int, val y: Int) record Point( int x, int y) { } 

record Point( int x, int y) { } data class Point( val x: Int, val y: Int) 

record Point( int x, int y) { } data class Point( val x: Int, val y: Int) 

record Point( int x, int y) { } @JvmRecord data class Point( val x: Int, val y: Int) 

record Point( int x, int y) { } @JvmRecord data class Point( val x: Int, val y: Int) 

record Point( int x, int y) { } @JvmRecord data class Point( val x: Int, val y: Int) 

record Point( int x, int y) { } var point = new Point(10, 20); // (10, 20) @JvmRecord data class Point( val x: Int, val y: Int) val point = Point(10, 20) // (10, 20) 

record Point( int x, int y) { } var point = new Point(10, 20); // (10, 20) @JvmRecord data class Point( val x: Int, val y: Int) val point = Point(10, 20) // (10, 20) val newPoint = point.copy(20) // (20, 20) 

record Point( int x, int y) { } var point = new Point(10, 20); // (10, 20) @JvmRecord data class Point( val x: Int, val y: Int) val point = Point(10, 20) // (10, 20) val newPoint = point.copy(20) // (20, 20) With Expressions (JEP 468) 

record Point( int x, int y) { } var point = new Point(10, 20); // (10, 20) var newPoint = point with { x = 20 } // (20, 20) @JvmRecord data class Point( val x: Int, val y: Int) val point = Point(10, 20) // (10, 20) val newPoint = point.copy(20) // (20, 20) With Expressions (JEP 468) 

Is Java always playing catch-up With Kotlin? 

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The Bytecode 

@JvmRecord data class Point( val x: Int, val y: Int) 

public String toString(); public int hashCode(); public boolean equals(Object); @JvmRecord data class Point( val x: Int, val y: Int) 

public String toString(); public int hashCode(); public boolean equals(Object); @JvmRecord data class Point( val x: Int, val y: Int) 

public String toString(); public int hashCode(); public boolean equals(Object); @JvmRecord data class Point( val x: Int, val y: Int) 

public String toString(); public int hashCode(); public boolean equals(Object); @JvmRecord data class Point( val x: Int, val y: Int) 

public String toString(); Code: 0: new #34 / / class StringBuilder 3: dup 4: invokespecial #35 / / Method StringBuilder 7: ldc #37 / / String Point(x= 9: invokevirtual #41 / / Method StringBuilder 12: aload_0 13: getfield #13 // Field x:I 16: invokevirtual #44 // Method StringBuilde 19: ldc #46 // String , y= 21: invokevirtual #41 // Method StringBuilde 24: aload_0 25: getfield #16 // Field y:I 28: invokevirtual #44 // Method StringBuilde 31: bipush 41 33: invokevirtual #49 // Method StringBuilde 36: invokevirtual #51 // Method StringBuilde 39: areturn @JvmRecord data class Point( val x: Int, val y: Int) 

public String toString(); Code: 0: new #34 / / class StringBuilder 3: dup 4: invokespecial #35 / / Method StringBuilder 7: ldc #37 / / String Point(x= 9: invokevirtual #41 / / Method StringBuilder 12: aload_0 13: getfield #13 // Field x:I 16: invokevirtual #44 // Method StringBuilde 19: ldc #46 // String , y= 21: invokevirtual #41 // Method StringBuilde 24: aload_0 25: getfield #16 // Field y:I 28: invokevirtual #44 // Method StringBuilde 31: bipush 41 33: invokevirtual #49 // Method StringBuilde 36: invokevirtual #51 // Method StringBuilde 39: areturn @JvmRecord data class Point( val x: Int, val y: Int) 

public int hashCode(); Code: 0: aload_0 1: getfield #13 / / Field x:I 4: invokestatic #57 / / Method java/lang/Int 7: istore_1 8: iload_1 9: bipush 31 11: imul 12: aload_0 13: getfield #16 // Field y:I 16: invokestatic #57 // Method java/lang/In 19: iadd 20: istore_1 21: iload_1 22: ireturn @JvmRecord data class Point( val x: Int, val y: Int) 

public int hashCode(); Code: 0: aload_0 1: getfield #13 / / Field x:I 4: invokestatic #57 / / Method java/lang/Int 7: istore_1 8: iload_1 9: bipush 31 11: imul 12: aload_0 13: getfield #16 // Field y:I 16: invokestatic #57 // Method java/lang/In 19: iadd 20: istore_1 21: iload_1 22: ireturn @JvmRecord data class Point( val x: Int, val y: Int) 

public boolean equals(Object); Code: 0: aload_0 1: aload_1 2: if_acmpne 7 5: iconst_1 6: ireturn 7: aload_1 8: instanceof #2 // class org/acme/Point 11: ifne 16 14: iconst_0 15: ireturn 16: aload_1 17: checkcast #2 // class org/acme/Point 20: astore_2 21: aload_0 22: getfield #13 // Field x:I 25: aload_2 26: getfield #13 // Field x:I 29: if_icmpeq 34 32: iconst_0 33: ireturn 34: aload_0 35: getfield #16 // Field y:I 38: aload_2 39: getfield #16 // Field y:I 42: if_icmpeq 47 45: iconst_0 46: ireturn 47: iconst_1 48: ireturn @JvmRecord data class Point( val x: Int, val y: Int) 

public boolean equals(Object); Code: 0: aload_0 1: aload_1 2: if_acmpne 7 5: iconst_1 6: ireturn 7: aload_1 8: instanceof #2 // class org/acme/Point 11: ifne 16 14: iconst_0 15: ireturn 16: aload_1 17: checkcast #2 // class org/acme/Point 20: astore_2 21: aload_0 22: getfield #13 // Field x:I 25: aload_2 26: getfield #13 // Field x:I 29: if_icmpeq 34 32: iconst_0 33: ireturn 34: aload_0 35: getfield #16 // Field y:I 38: aload_2 39: getfield #16 // Field y:I 42: if_icmpeq 47 45: iconst_0 46: ireturn 47: iconst_1 48: ireturn @JvmRecord data class Point( val x: Int, val y: Int) 

record Point( int x, int y) { } 

record Point( int x, int y) { } public String toString(); public int hashCode(); public boolean equals(Object); 

record Point( int x, int y) { } public String toString(); public int hashCode(); public boolean equals(Object); 

record Point( int x, int y) { } public String toString(); public int hashCode(); public boolean equals(Object); 

record Point( int x, int y) { } public String toString(); public int hashCode(); public boolean equals(Object); 

public final String toString(); Code: 0: aload_0 1: invokedynamic #19, 0 6: areturn record Point( int x, int y) { } 

public final String toString(); Code: 0: aload_0 1: invokedynamic #19, 0 6: areturn record Point( int x, int y) { } 

record Point( int x, int y) { } public final int hashCode(); Code: 0: aload_0 1: invokedynamic #23, 0 6: ireturn 

record Point( int x, int y) { } public final int hashCode(); Code: 0: aload_0 1: invokedynamic #23, 0 6: ireturn 

record Point( int x, int y) { } public final boolean equals(Obje Code: 0: aload_0 1: aload_1 2: invokedynamic #27, 0 7: ireturn 

record Point( int x, int y) { } public final boolean equals(Obje Code: 0: aload_0 1: aload_1 2: invokedynamic #27, 0 7: ireturn 

So what’s the difference? 

Java Records can take advantage of the JVM’s implementation and future improvements for the toString, equals & hashCode methods without recompiling. 

In a lot of cases Kotlin is playing catch-up with Java