We try to keep our books accurate, but sometimes mistakes creep in. This page lists the errors submitted by our astute readers. If you've found a new error, please submit it.

The latest version of the book is P1.0, released almost 8 years ago. If you've bought a PDF of the book and would like to upgrade it to this version (for free), visit your home page.

Key: Typo Tech. Error Suggestion Not a problem Next edition

By default this page displays the errata for the latest version of the book. If you have a previous version, select it here:  

(To find out what version you have, look at the copyright page, a few pages in from the front of the book. If it says (say) 'Second Printing', then here it'll be P2.0. If there are interim PDF releases in that printing, they'll be 2.1, 2.2, and so on.)

PDF Paper Description Found in Fixed in
all
#25379: The "Report erratum" link is wrong! http://books.pragprog.com/title/fr_j2r/errata/add?pdf_page=16 should be http://books.pragprog.com...more...
P1.0
02-Jul-06
15

#28882: Figure 1.1 has a timeline that goes from
1950
1960
1970
1980
1900 -- should be 1990
2000--Jason Vinson

P1.0
01-May-07
16
#25378: In the 3rd paragraph of the "The Hierarchy of Pain" section: "too many ve...more...
P1.0
02-Jul-06
17
#27903: "The inventor of SPC, Edward Walter Demming ..." is certainly incorrect. See the reference in Wikipedia for "William Edwards Deming". I origin...more...
P1.0
22-Mar-07
20
#25990: The third bullet near the bottom of the page contains the sentence "Similar Java programs have to deal with objects, but also characters, numb...more...
P1.0
26-Sep-06
50
#25463: "But learning an integrated development language, such as Eclipse..." In this context, it seems "development tool" would be more appropriate t...more...
P1.0
17-Jul-06
57
#25787: Second sentence under 3.6 Looking Ahead reads "Many Java visionaries are leaving the Java community to gear up for Java development" Shouldn't...more...
P1.0
26-Aug-06
58
#25464: "Many Java visionaries are leaving the Java community to gear up for Java development." I suspect the last two words were supposed to be "Rub...more...
P1.0
17-Jul-06
73
#25465: The heading for section 4.5 is "Scenario 4: Bet-your-Business: Basecamp" but the text for section 4.5 does not explain what Basecamp is, nor d...more...
P1.0
17-Jul-06
85

#25407: Velocity has nothing to do with database wrappers - it is a view technology.--Michiel de Mare

P1.0
07-Jul-06
97
#25466: "If you're building a user interface in Ruby that merely submits simple forms and accessing a Java back end..." should use "accesses" instead ...more...
P1.0
17-Jul-06
108
#25467: The heading for section 6.3 is "Ruby to Java Bridges" but the first sentence on the section contains the phrase "Java to Ruby bridge solutions...more...
P1.0
17-Jul-06
110
#25989: The sentence of the second bullet point just below the middle of the page ("Use Java frameworks from within the Ruby langauge.") ends with "la...more...
P1.0
26-Sep-06
112

#25468: "We have working prototypes of servlets for running run Ruby we applications..." the word "run" is not needed.--Gregg Sporar

P1.0
17-Jul-06
113
#25469: "As we saw in the interview, JRuby is a Ruby virtual machine, written in Ruby..." But in the answer to the first question, Charles Nutter sta...more...
P1.0
17-Jul-06
115

#25470: "Keep in mind that today, JRuby is under heavy development, and would be an agressive move..." The word "it" should be inserted in front of "would"--Gregg Sporar

P1.0
17-Jul-06
120
#25471: "This flow represents the way the Web has worked for decades." Using the word "decades" suggests 20 years or more. HTTP has only been around...more...
P1.0
17-Jul-06
133
#25472: "For example, the people database holds person objects." Since this is in the context of naming tables, shouldn't the sentence be: "For examp...more...
P1.0
17-Jul-06
133
#25473: "In Active Record, a row named person_id would point to a row in the people database." It seems like the sentence should be: "In Active Recor...more...
P1.0
17-Jul-06
143

#25474: "... powered by the success of it's flagship framework, Ruby on Rails." The "it's" should be "its"--Gregg Sporar

P1.0
17-Jul-06