Corrections to Chapter 1 of Java I/O, Introducing I/O

p. 9: In the middle of the page, the arithmetic algorithm given for finding the last byte of the number is incorrect for negative numbers. That section should read like this:

This is the effect of taking the remainder modulo 256 of the int b and adding 256 if the value is negative; that is,
b = b % 256 >= 0 ? b % 256 : 256 + b % 256;
More simply, using bitwise operators,
b = b & 0x000000FF;

p. 10: In the line of code near the top of the page the greater than sign should be greater than or equals; that is,

 int unsignedByte = signedByte >= 0 ? signedByte : 256 + signedByte;

p. 10: In the fifth paragraph change "the absolute value of the number" to "The absolute value of a negative number"

p. 13: EBCDIC is more often an eight-bit character set than a seven-bit set (but only IBM knows for sure in all the different versions of EBCDIC that exist)

p. 21: In the second paragraph of the System.out section change "Hello World" to "Hello World!"

p. 23: In the first paragraph on the page, change

For example, if the user types "Hello World", the following bytes will be read from System.in in this order:

For example, if the user types "Hello World!" and hits the return or enter key, the following bytes will be read from System.in in this order:

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