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ChrisMayfieldChrisMayfield
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reviewed ch09
1 parent f484141 commit 353ee38

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‎appe/Tables.java‎

Lines changed: 61 additions & 0 deletions
Original file line numberDiff line numberDiff line change
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/**
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* Generating tables.
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*/
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public class Tables {
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public static void example() {
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int i = 1;
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while (i < 10) {
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double x = i;
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System.out.println(x + " " + Math.log(x));
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i = i + 1;
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}
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}
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public static void example2() {
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int i = 1;
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while (i < 10) {
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double x = i;
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System.out.println(x + " " + Math.log(x) / Math.log(2));
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i = i + 1;
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}
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}
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public static void example3() {
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final double LOG2 = Math.log(2);
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int i = 1;
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while (i < 100) {
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double x = i;
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System.out.println(x + " " + Math.log(x) / LOG2);
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i = i * 2;
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}
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}
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public static void main(String[] args) {
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System.out.println("example");
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example();
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System.out.println("example2");
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example2();
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System.out.println("example3");
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example3();
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}
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}
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public static void printTable4(int rows) {
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for (int i = 1; i <= rows; i = i + 1) {
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printRow3(i, rows);
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}
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}
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public static void printRow4(int n, int cols) {
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int i;
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for (i = 1; i <= cols; i = i + 1) {
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System.out.printf("%4d", n * i);
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}
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System.out.println(i);
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}
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‎ch09/Max.java‎

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Original file line numberDiff line numberDiff line change
@@ -11,6 +11,11 @@ public class Max {
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public static void main(String[] args) {
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System.out.println(Arrays.toString(args));
1313

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if (args.length == 0) {
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System.err.println("Usage: java Max <numbers>");
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return;
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}
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int max = Integer.MIN_VALUE;
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for (String arg : args) {
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int value = Integer.parseInt(arg);

‎ch09/Objects.java‎

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import java.math.BigInteger;
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/**
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* Demonstates uses of objects and wrappers.
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*/
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public class Objects {
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public static void main(String[] args) {
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// primitives vs objects
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int number = -2;
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char symbol = '!';
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char[] array = {'c', 'a', 't'};
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String word = "dog";
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// Strings are immutable
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String name = "Alan Turing";
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String upperName = name.toUpperCase();
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String text = "Computer Science is fun!";
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text = text.replace("Computer Science", "CS");
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// Wrapper classes
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Integer x = new Integer(123);
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Integer y = new Integer(123);
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if (x == y) { // false
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System.out.println("x and y are the same object");
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}
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if (x.equals(y)) { // true
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System.out.println("x and y have the same value");
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}
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String str = "12345";
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int num = Integer.parseInt(str);
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num = 12345;
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str = Integer.toString(num);
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// BigInteger arithmetic
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long z = 17;
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BigInteger big = BigInteger.valueOf(z);
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String s = "12345678901234567890";
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BigInteger bigger = new BigInteger(s);
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BigInteger a = BigInteger.valueOf(17);
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BigInteger b = BigInteger.valueOf(1700000000);
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BigInteger c = a.add(b);
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}
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}

ch09/Exercise.java renamed to ch09/Parens.java

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1,7 +1,7 @@
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/**
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* Exercise on encapsulation and generalization.
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*/
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public class Exercise {
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public class Parens {
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public static void main(String[] args) {
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String s = "((3 + 7) * 2)";

ch10/Pow.java renamed to ch09/Pow.java

File renamed without changes.

‎ch09/Tables.java‎

Lines changed: 21 additions & 101 deletions
Original file line numberDiff line numberDiff line change
@@ -1,45 +1,8 @@
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/**
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* Generating tables; encapsulation and generalization.
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* Encapsulation and generalization.
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*/
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public class Tables {
55

6-
public static void example() {
7-
int i = 1;
8-
while (i < 10) {
9-
double x = i;
10-
System.out.println(x + " " + Math.log(x));
11-
i = i + 1;
12-
}
13-
}
14-
15-
public static void example2() {
16-
int i = 1;
17-
while (i < 10) {
18-
double x = i;
19-
System.out.println(x + " " + Math.log(x) / Math.log(2));
20-
i = i + 1;
21-
}
22-
}
23-
24-
public static void example3() {
25-
final double LOG2 = Math.log(2);
26-
int i = 1;
27-
while (i < 100) {
28-
double x = i;
29-
System.out.println(x + " " + Math.log(x) / LOG2);
30-
i = i * 2;
31-
}
32-
}
33-
34-
public static void example4() {
35-
int i = 1;
36-
while (i <= 6) {
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System.out.printf("%4d", 2 * i);
38-
i = i + 1;
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}
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System.out.println();
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}
42-
436
public static void printRow() {
447
int i = 1;
458
while (i <= 6) {
@@ -49,109 +12,66 @@ public static void printRow() {
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System.out.println();
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}
5114

52-
public static void printRow2(int n) {
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public static void printRow(int n) {
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int i = 1;
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while (i <= 6) {
55-
System.out.printf("%4d", n * i);
18+
System.out.printf("%4d", n * i); // generalized n
5619
i = i + 1;
5720
}
5821
System.out.println();
5922
}
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61-
public static void example5() {
62-
int i = 1;
63-
while (i <= 6) {
64-
printRow2(i);
65-
i = i + 1;
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}
67-
}
68-
6924
public static void printTable() {
7025
int i = 1;
7126
while (i <= 6) {
72-
printRow2(i);
27+
printRow(i);
7328
i = i + 1;
7429
}
7530
}
7631

77-
public static void printTable2(int rows) {
32+
public static void printTable(int rows) {
7833
int i = 1;
79-
while (i <= rows) {
80-
printRow2(i);
34+
while (i <= rows) { // generalized rows
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printRow(i);
8136
i = i + 1;
8237
}
8338
}
8439

85-
public static void printRow3(int n, int cols) {
40+
public static void printRow(int n, int cols) {
8641
int i = 1;
87-
while (i <= cols) {
42+
while (i <= cols) { // generalized cols
8843
System.out.printf("%4d", n * i);
8944
i = i + 1;
9045
}
9146
System.out.println();
9247
}
9348

94-
public static void printTable3(int rows) {
49+
public static void printTable2(int rows) {
9550
int i = 1;
9651
while (i <= rows) {
97-
printRow3(i, rows);
52+
printRow(i, rows); // added rows argument
9853
i = i + 1;
9954
}
10055
}
10156

102-
public static void printTable4(int rows) {
103-
for (int i = 1; i <= rows; i = i + 1) {
104-
printRow3(i, rows);
105-
}
106-
}
107-
108-
public static void printRow4(int n, int cols) {
109-
int i;
110-
for (i = 1; i <= cols; i = i + 1) {
111-
System.out.printf("%4d", n * i);
112-
}
113-
System.out.println(i);
114-
}
115-
11657
public static void main(String[] args) {
117-
System.out.println("example");
118-
example();
119-
120-
System.out.println("example2");
121-
example2();
122-
123-
System.out.println("example3");
124-
example3();
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126-
System.out.println("example4");
127-
example4();
128-
129-
System.out.println("example5");
130-
example5();
131-
132-
System.out.println("printRow");
58+
System.out.println("printRow()");
13359
printRow();
13460

135-
System.out.println("printRow2");
136-
printRow2(6);
61+
System.out.println("printRow(6)");
62+
printRow(6);
13763

138-
System.out.println("printTable");
64+
System.out.println("printTable()");
13965
printTable();
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141-
System.out.println("printTable2");
142-
printTable2(6);
143-
144-
System.out.println("printRow3");
145-
printRow3(6, 6);
146-
147-
System.out.println("printTable3");
148-
printTable3(6);
67+
System.out.println("printTable(6)");
68+
printTable(6);
14969

150-
System.out.println("printRow4");
151-
printRow4(6, 6);
70+
System.out.println("printRow(6, 6)");
71+
printRow(6, 6);
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153-
System.out.println("printTable4");
154-
printTable4(6);
73+
System.out.println("printTable2(6)");
74+
printTable2(6);
15575
}
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15777
}

‎ch09/Things.java‎

Lines changed: 0 additions & 32 deletions
This file was deleted.

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