Errata OCP Java SE 11 Programmer I Study Guide (Sybex Appendix A - p.506) from Jeanne and Scott

[Amir Shah]

The following paragraph is taken from OCP Java  SE 11 Programmer I Study Guide (Sybex Appendix A - p.506) from Jeanne boyarsky and Scott Selikoff

The first line in the last paragraph says

For the second part, a += 2 expands to a = a + 2.

It should be

For the second part, s2 += 2 expands tos2 = s2 + 2.

Muhammad Shah
https://www.youtube.com/channel/UCZC5KfHgb_nQVedKY0MMhLw?view_as=subscriber

[Campbell Ritchie]

Please avoid coloured text, which many people can't read. I have changed your text to black.
Why is that an error? B&S are using a as a generic variable name.

[Amir Shah]

Campbell Ritchie wrote:Please avoid coloured text, which many people can't read. I have changed your text to black.
Why is that an error? B&S are using a as a generic variable name.

They are not using "a" as generic variable name. Please read the following question of OCP Java  SE 11 Programmer I Study Guide (Sybex Ch-5 - p.213) from Jeanne boyarsky and Scott Selikoff

9. What is the result of the following code? (Choose all that apply.)

14: String s1 = "purr";
15: String s2 = "";
16:
17: s1.toUpperCase();
18: s1.trim();
19: s1.substring(1, 3);
20: s1 += "two";
21:
22: s2 += 2;
23: s2 += 'c';
24: s2 += false;
25:
26: if ( s2 == "2cfalse") System.out.println("==");
27: if ( s2.equals("2cfalse")) System.out.println("equals");
28: System.out.println(s1.length());

A. 2
B. 4
C. 7
D. 10
E. ==
F. equals
G. An exception is thrown.
H. The code does not compile.

They are trying to explain line 22 In the Appendix A - p. 506 but using the wrong variable a instead of s2.

The first line in the last paragraph says

For the second part, a += 2 expands to a = a + 2.

It should be

For the second part, s2 += 2 expands to s2 = s2 + 2.

[Jeanne Boyarsky]

Agreed this is a typo. Added to errata list.