small refactor

app/src/main/java/chess/model/pieces/Bishop.java

@@ -15,13 +15,4 @@ public class Bishop extends Piece {
 		return visitor.visitPiece(this);
 	}
 
-	@Override
-	public int hashCode() {
-		return 0;
-	}
-
-	public boolean equals(Object obj) {
-		return (obj instanceof Bishop && ((Bishop) obj).getColor() == this.getColor());
-	}
-
 }

app/src/main/java/chess/model/pieces/King.java

@@ -14,13 +14,4 @@ public class King extends Piece {
 	public <T> T accept(PieceVisitor<T> visitor) {
 		return visitor.visitPiece(this);
 	}
-
-	@Override
-	public int hashCode() {
-		return 1;
-	}
-
-	public boolean equals(Object obj) {
-		return (obj instanceof King && ((King) obj).getColor() == this.getColor());
-	}
 }

app/src/main/java/chess/model/pieces/Knight.java

@@ -15,12 +15,4 @@ public class Knight extends Piece {
 		return visitor.visitPiece(this);
 	}
 
-	@Override
-	public int hashCode() {
-		return 2;
-	}
-
-	public boolean equals(Object obj) {
-		return (obj instanceof Knight && ((Knight) obj).getColor() == this.getColor());
-	}
 }

app/src/main/java/chess/model/pieces/Pawn.java

@@ -19,12 +19,4 @@ public class Pawn extends Piece {
 		return getColor() == Color.White ? 1 : -1;
 	}
 
-	@Override
-	public int hashCode() {
-		return 3;
-	}
-
-	public boolean equals(Object obj) {
-		return (obj instanceof Pawn && ((Pawn) obj).getColor() == this.getColor());
-	}
 }

app/src/main/java/chess/model/pieces/Queen.java

@@ -15,12 +15,5 @@ public class Queen extends Piece {
 		return visitor.visitPiece(this);
 	}
 
-	@Override
-	public int hashCode() {
-		return 4;
-	}
 
-	public boolean equals(Object obj) {
-		return (obj instanceof Queen && ((Queen) obj).getColor() == this.getColor());
-	}
 }

app/src/main/java/chess/model/pieces/Rook.java

@@ -15,12 +15,4 @@ public class Rook extends Piece {
 		return visitor.visitPiece(this);
 	}
 
-	@Override
-	public int hashCode() {
-		return 5;
-	}
-
-	public boolean equals(Object other) {
-		return (other instanceof Rook && ((Rook) other).getColor() == this.getColor());
-	}
 }