---
title: JAVA(進階程設-期中考後)
tags: JAVA(進階程設-期中考後)
---
# JAVA程式語言 --- 李鍾斌(進階程設-期中考後)
> 【目次】
> [TOC]
>
---
## 期中考解答 PDF
:::success
### Q01
```java=
import java.io.*;
public class Exam01 {
public static void main(String[] args) {
try{
FileReader fr = new FileReader("in.txt");
BufferedReader br = new BufferedReader(fr);
FileWriter fw = new FileWriter("out.txt", false);
BufferedWriter bw = new BufferedWriter(fw);
String line;
int i = 0;
System.out.println("Name Math English");
String linelist [] = new String [4]; //宣告0,1,2,3
while ((line = br.readLine()) != null) {
linelist[i] = line;
System.out.println(linelist[i]); //使用0,1,2
i++;
}
bw.write("Name Math English");
bw.newLine();
for (int j = 2; j >= 0; j--){ //寫入2,1,0
bw.write(linelist[j]);
bw.newLine();
}
bw.close();
} catch (IOException e) { System.out.println(e);}
}
}
```
```java=
public class CScore {
String name; int math; int eng;
public CScore (){
}
public CScore (String str, int m, int e){
name = str;
math = m;
eng = e;
}
}
```
:::
:::warning
### Q02
```java=
public class CAdd {
public static void main(String[] args) {
CAddto ad1 = new CAddto();
CAddto ad2 = new CAddto(15);
ad1.add();
ad2.add();
}
}
```
```java=
public class CAddto extends CAdd {
int upper;
public CAddto(){
upper = 10;
}
public CAddto(int a){
upper = a;
}
public void add(){
int sum = 0;
for (int i = 0; i <= upper; i++){
sum += i;
}
System.out.printf("1+2+...+%d=%d\n", upper, sum);
}
}
```
:::
:::info
### Q03
```java=
import java.util.*;
public class Exam03 {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.printf("=== 第一位 ===\n"); //第一組 日期資料
BDate bd1 = new BDate();
System.out.printf("year = "); bd1.year = sc.nextInt();
System.out.printf("month = "); bd1.month = sc.nextInt();
System.out.printf("day = "); bd1.day = sc.nextInt();
bd1.calAge(bd1.year); //印出 "年齡"
bd1.printDate(bd1.year, bd1.month, bd1.day);
bd1.leap(bd1.year); //印出 "平/閏年"
System.out.printf("\n=== 第二位 ===\n"); //第二組 日期資料
BDate bd2 = new BDate();
System.out.printf("year = "); bd2.year = sc.nextInt();
System.out.printf("month = "); bd2.month = sc.nextInt();
System.out.printf("day = "); bd2.day = sc.nextInt();
bd2.calAge(bd2.year);
bd2.printDate(bd2.year, bd2.month, bd2.day);
bd2.leap(bd2.year);
System.out.printf("\n=== 第三位 ===\n"); //第三組 日期資料
BDate bd3 = new BDate();
bd3.year = 1990; bd3.month = 1; bd3.day = 1;
bd3.calAge(bd3.year);
bd3.printDate(bd3.year, bd3.month, bd3.day);
bd3.leap(bd3.year);
sortAge(bd1.year, bd2.year, bd3.year);
}
public static void sortAge(int a, int b, int c){
//印出年齡最大的一位。用西元年來比較
System.out.printf("\n=== 年齡最大者 ===\n");
if (a < b && a < c){
System.out.println("第一位");
} else if (b < a && b < c){
System.out.println("第二位");
} else if (c < a && c < b) {
System.out.println("第三位");
}
}
}
Output:
=== 第一位 ===
year = 1880
month = 3
day = 4
年齡：139
Year Month Day
1880 3 4
閏年
=== 第二位 ===
year = 1840
month = 5
day = 4
年齡：179
Year Month Day
1840 5 4
閏年
=== 第三位 ===
年齡：29
Year Month Day
1990 1 1
平年
=== 年齡最大者 ===
第二位
```
```java=
public class BDate {
int year, month, day;
int age; //年齡，在排序時用來比較
public BDate(){
int year = 1990; int month = 1; int day = 1;
}
public int calAge(int y){ //計算年齡(計算至今日的實際歲數，只計年不計月)
int age;
age = 2019 - y;
System.out.println("年齡：" + age);
return age;
}
public void printDate(int y, int m, int d){ //列印日期資料
System.out.printf("Year\t Month\t Day\n");
System.out.println(y + "\t " + m + "\t " + d + "\n");
}
public void leap (int y){ //判斷並列印變數year是否為閏年：boolean
if (y % 4 != 0)
System.out.println("平年");
else{
if (y % 100 != 0)
System.out.println("閏年");
else{
if (y % 400 != 0)
System.out.println("平年");
else
System.out.println("閏年");
}
}
}
}
```
:::
# 2019-04-22 class
* 動態陣列 vs. 之前介紹的Array(必須宣告空間有多大)
* 動態陣列
* 優點：不需事先宣告空間有多大
* 缺點：比傳統的陣列慢、效率差。
* 傳統的陣列 (之前介紹的Array)
* 缺點：必須事先宣告空間有多大
## Java 資料處理 -- ==讀取數值==
* 資料集：`test.txt`
```
170.0 80.0 90.5
172.5 67.2 81.4
210.1 104.9 100.3
```
* 以"空格/tab"分開，將每個元素分別放進 tempArray
```java=
tempArray = tempstring.split("\\s"); //以"空格"分開
tempArray = tempstring.split("\\t"); //以"tab"分開
```
```java=
import java.io.*;
import java.util.ArrayList;
public class Week10 {
public static void main(String[] args) {
try{
FileReader fr = new FileReader("in.txt");
BufferedReader br = new BufferedReader(fr);
String line, tempstring;
String [] tempArray = new String[3]; //宣告0,1,2
ArrayList myList = new ArrayList();
int i = 0;
//每次讀取一整行 170.0 80.0 90.5
while ( (line = br.readLine()) != null ){
tempstring = line;
tempArray = tempstring.split("\\s");
//System.out.println(tempArray[0]+"===");
//170.0=== //172.5=== //210.1===
for (i = 0; i < tempArray.length; i++){
myList.add(tempArray[i]);
//System.out.println(tempArray[i]+"---");
//170.0--- //80.0--- //90.5--- ...
}
}
//動態陣列 .size() = 傳統陣列 .length()
int k = myList.size()/3; //k = 3組
int count = 0;
double [][] trans_array = new double [k][3];
for ( int x = 0; x < k; x++){
for (int y = 0; y < 3; y++){
trans_array[x][y] = Double.parseDouble((String)myList.get(count));
count++;
System.out.println(trans_array[x][y]);
}
}
System.out.println("----- Data Imported ------");
for ( int x = 0; x < k; x++){
for (int y = 0; y < 3; y++){
System.out.printf("%5.1f\t", trans_array[x][y]);
}
System.out.println();
}
} catch (IOException e) { System.out.println(e);}
}
}
Output:
> run Week10
170.0
80.0
90.5
172.5
67.2
81.4
210.1
104.9
100.3
----- Data Imported ------
170.0 80.0 90.5
172.5 67.2 81.4
210.1 104.9 100.3
```
---
# 2019-04-29 class
## Java 資料處理 -- ==讀取數值&字串==
* 資料集： `irisdata .txt`
```
5.1 3.5 1.4 0.2 setosa
4.9 3.0 1.4 0.2 setosa
4.7 3.2 1.3 0.2 setosa
4.6 3.1 1.5 0.2 setosa
5.0 3.6 1.4 0.2 setosa
...
```
```java=
import java.io.*;
import java.util.ArrayList;
public class Week11 {
public static void main(String[] args) {
try{
FileReader fr = new FileReader("irisdata.txt");
BufferedReader br = new BufferedReader(fr);
String line, tempstring;
String [] tempArray = new String[5]; //宣告0,1,2,3,4
ArrayList myList = new ArrayList();
int i = 0;
//每次讀取一整行 5.1 3.5 1.4 0.2 setosa
while ( (line = br.readLine()) != null ){
tempstring = line;
tempArray = tempstring.split("\\t");
//System.out.println(tempArray[0]+"===");
//5.1=== //4.9=== //4.7=== ...
for (i = 0; i < tempArray.length; i++){
myList.add(tempArray[i]);
//System.out.println(tempArray[i]+"---");
//5.1--- //3.5--- //1.4--- //0.2--- //setosa--- ...
}
}
//動態陣列 .size() = 傳統陣列 .length()
int k = myList.size()/5; //k 組 //第 k 列 (橫)
int count = 0;
double [][] trans_array = new double [k][4]; //for 5.1 3.5 1.4 0.2
String [] str_trans_array = new String [k]; //for setosa
for ( int x = 0; x < k; x++){
for (int y = 0; y < 4; y++){
trans_array[x][y] = Double.parseDouble((String)myList.get(count));
count++;
}
str_trans_array[x] = (String)myList.get(count);
count++;
}
System.out.println("-------- Data Imported ---------");
System.out.printf("花萼長度\t花萼寬度\t花瓣長度\t花瓣寬度\t屬種\n");
for ( int x = 0; x < k; x++){
System.out.printf("%5.1f\t%5.1f\t%5.1f\t%5.1f\t%s\n",
trans_array[x][0], trans_array[x][1], trans_array[x][2],
trans_array[x][3], str_trans_array[x]);
}
} catch (IOException e) { System.out.println(e); }
}
}
Output:
-------- Data Imported ---------
花萼長度 花萼寬度 花瓣長度 花瓣寬度 屬種
5.1 3.5 1.4 0.2 setosa
4.9 3.0 1.4 0.2 setosa
...
```
* K-近鄰演算法 (K Nearest Neighbor, KNN)：k個最近的鄰居
:::warning
## HW07：鳶尾花分類 (1NN)
1.利用課堂範例，將irisdata.txt匯入程式。
2.採用kNN方法(k=1)，讓使用者由鍵盤輸入資料後判斷所屬亞種。
```java=
import java.util.*;
import java.io.*;
import java.util.ArrayList;
public class Week10 {
public static void main(String[] args) {
try{
FileReader fr = new FileReader("irisdata.txt");
BufferedReader br = new BufferedReader(fr);
String line, tempstring;
String [] tempArray = new String[5]; //宣告0,1,2,3,4
ArrayList myList = new ArrayList();
int i = 0;
//每次讀取一整行 5.1 3.5 1.4 0.2 setosa
while ( (line = br.readLine()) != null ){
tempstring = line;
tempArray = tempstring.split("\\t");
//System.out.println(tempArray[0]+"===");
//5.1=== //4.9=== //4.7=== ...
for (i = 0; i < tempArray.length; i++){
myList.add(tempArray[i]);
//System.out.println(tempArray[i]+"---");
//5.1--- //3.5--- //1.4--- //0.2--- //setosa--- ...
}
}
//動態陣列 .size() = 傳統陣列 .length()
int k = myList.size()/5; //k 組 //第 k 列 (橫)
int count = 0;
//for 5.1 3.5 1.4 0.2
double [][] trans_array = new double [k][4];
//for setosa
String [] str_trans_array = new String [k];
for ( int x = 0; x < k; x++){
for (int y = 0; y < 4; y++){
trans_array[x][y] = Double.parseDouble((String)myList.get(count));
count++;
}
str_trans_array[x] = (String)myList.get(count);
count++;
}
/* --- 使用者 input (1筆) --- */
System.out.println("請輸入 一筆 未知鳶尾花的資料");
Double [] unknown = new Double[4]; //0,1,2,3
Scanner sc = new Scanner(System.in);
System.out.printf("花萼長度："); unknown [0] = sc.nextDouble();
System.out.printf("花萼寬度："); unknown [1] = sc.nextDouble();
System.out.printf("花瓣長度："); unknown [2] = sc.nextDouble();
System.out.printf("花瓣寬度："); unknown [3] = sc.nextDouble();
/*
String [] kind = new String [1]; //0
System.out.printf("請輸入花萼屬種：");
kind[0] = sc.next();
System.out.printf(kind[0]+'\n');
*/
// KNN, k=1
// 計算"每組(每一橫列)"與"使用者 input"之差的平方和。共 k 組
Double [] iris_all = new Double [k];
for ( int x = 0; x < k; x++){
iris_all[x] = Math.sqrt(
Math.pow(trans_array[x][0] - unknown[0], 2) +
Math.pow(trans_array[x][1] - unknown[1], 2) +
Math.pow(trans_array[x][2] - unknown[2], 2) +
Math.pow(trans_array[x][3] - unknown[3], 2) );
count++;
}
int index = 1; //實際上為第幾筆
Double min = iris_all[0];
for (int j = 0; j < k; j++) {
if (iris_all[j] < min) { //如果該筆資料<目前最低分
min = iris_all[j]; //該筆設為目前最低分
index = j + 1;
System.out.printf("%.5f\n", iris_all[j]);
}
}
System.out.printf("KNN k = 1 =>\n");
System.out.printf(
"該資料為第 %2d筆：\n%5.1f\t%5.1f\t%5.1f\t%5.1f\t%s\n",
index, trans_array[index-1][0], trans_array[index-1][1],
trans_array[index-1][2], trans_array[index-1][3],
str_trans_array[index-1]);
} catch (IOException e) { System.out.println(e);}
}
}
Output:
請輸入 一筆 未知鳶尾花的資料
花萼長度：5.10001
花萼寬度：3.4
花瓣長度：1.5
花瓣寬度：0.2
0.10001
0.00001
KNN k = 1 =>
該資料為第 40筆：
5.1 3.4 1.5 0.2 setosa
```
:::
---
# 2019-05-06 class
## Eclipse Java Photon ==Java==
* Create Java 【Project：proj】 -> 【Class：Test】
* 改變【字體大小】
## ==Window Builder 1.9.1==
* 安裝：help -> Eclipse Marketplace -> Search "Window Builder" -> 【Window Builder 1.9.1】
* 建立：Create Java 【Project：WinTest】 -> New - ==【Other...】==
* -> WindowBuilder - Swing Designer - ==Application Window==
* JButton
* Set layout -> ==Absolute layout==
* Properties:
* 該按鈕真正的名字(Variable)
* 寫按鈕的事件：
* performed 點兩下後，把事件寫進按鈕裡。
:::success
## ==Window Builder -- BMI計算==
```java=
btnNewButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
double height = (Double.parseDouble(h1.getText()));
double weight = (Double.parseDouble(w2.getText()));
double bmi = weight/((height/100.0)*(height/100.0));
java.text.DecimalFormat df = new java.text.DecimalFormat("#.00");
String s = df.format(bmi);
bmi3.setText(s);
System.out.println(s);
}
});
```
---
### HW08：視窗化BMI計算
```java=
btnNewButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
double height = (Double.parseDouble(h1.getText()));
double weight = (Double.parseDouble(w2.getText()));
double bmi = weight/((height/100.0)*(height/100.0));
if (bmi < 20)
bmi_judge.setText("體重過輕");
else if (bmi < 25)
bmi_judge.setText("體重正常");
else if (bmi < 30)
bmi_judge.setText("體重過重");
else
bmi_judge.setText("go to see a doctor");
java.text.DecimalFormat df = new java.text.DecimalFormat("#.00");
String s = df.format(bmi);
bmi3.setText(s);
System.out.println(s);
}
});
```
:::
---
# 2019-05-13 class
## Window Builder
* Button：【請按...】
```java=
public void actionPerformed(ActionEvent e) {
int m = (Integer.parseInt(text1.getText())); //month
int d = (Integer.parseInt(text2.getText())); //day
if (m == 1 & (d >= 21 & d <= 31)) text3.setText("水瓶座");
if (m == 2 & (d >= 1 & d <= 19)) text3.setText("水瓶座");
if (m == 2 & (d >= 20 & d <= 29)) text3.setText("雙魚座");
if (m == 3 & (d >= 1 & d <= 20)) text3.setText("雙魚座");
if (m == 3 & (d >= 21 & d <= 31)) text3.setText("牡羊座");
if (m == 4 & (d >= 1 & d <= 20)) text3.setText("牡羊座");
if (m == 4 & (d >= 21 & d <= 30)) text3.setText("金牛座");
if (m == 5 & (d >= 1 & d <= 21)) text3.setText("金牛座");
if (m == 5 & (d >= 22 & d <= 31)) text3.setText("雙子座");
if (m == 6 & (d >= 1 & d <= 21)) text3.setText("雙子座");
if (m == 6 & (d >= 22 & d <= 30)) text3.setText("巨蟹座");
if (m == 7 & (d >= 1 & d <= 23)) text3.setText("巨蟹座");
if (m == 7 & (d >= 24 & d <= 31)) text3.setText("獅子座");
if (m == 8 & (d >= 1 & d <= 23)) text3.setText("獅子座");
if (m == 8 & (d >= 24 & d <= 31)) text3.setText("處女座");
if (m == 9 & (d >= 1 & d <= 23)) text3.setText("處女座");
if (m == 9 & (d >= 24 & d <= 30)) text3.setText("天枰座");
if (m == 10 & (d >= 1 & d <= 23)) text3.setText("天枰座");
if (m == 10 & (d >= 24 & d <= 31)) text3.setText("天蠍座");
if (m == 11 & (d >= 1 & d <= 22)) text3.setText("天蠍座");
if (m == 11 & (d >= 23 & d <= 30)) text3.setText("射手座");
if (m == 12 & (d >= 1 & d <= 22)) text3.setText("射手座");
if (m == 12 & (d >= 23 & d <= 31)) text3.setText("摩羯座");
if (m == 1 & (d >= 1 & d <= 22)) text3.setText("摩羯座");
}
```
* 一鍵清空
```java=
public void actionPerformed(ActionEvent e) {
text1.setText("");
text2.setText("");
text3.setText("");
}
```
---
## 打包Java程式
* File -> Export... -> Java - ==Runnable JAR file==
* 1 -> 打包成可執行檔(只有==執行檔==)
* 3 -> 打包成可執行檔 & 把外部函式庫也一併打包(==執行檔==+==外部函式庫==)
---
## 開啟檔案
```java=
import javax.swing.JFileChooser;
import java.io.File;
public void actionPerformed(ActionEvent e) {
JFileChooser fileChooser = new JFileChooser();
File selectedFile = null;
//叫出fileChooser
int returnValue = fileChooser.showOpenDialog(null);
//判斷是否選擇檔案
if (returnValue == JFileChooser.APPROVE_OPTION) {
selectedFile = fileChooser.getSelectedFile(); //指派給file
System.out.println(selectedFile.getName()); //印出檔名
text_file.setText(selectedFile.getName());
}
}
```
---
# 2019-05-20 class
## Window Builder (檔案處理 + 讀檔)
:::success
### HW09：視窗程式-檔案處理
* 程式要求：
1. 由FileChooser讓使用者自行選擇匯入資料檔
2. 再根據使用者鍵盤輸入之出生月日，計算資料檔中與使用者同星座的人數
* 檔案
```
Bessy 3 28
Ariel 5 2
Cindy 9 9
...
```
* 物件：`text_m` `text_d` `text3` `text4` `text_file`
* ==< Int to Str >==
```
1.) String s = String.valueOf(i);
2.) String s = Integer.toString(i);
3.) String s = "" + i;
````
```java=
import javax.swing.JFileChooser;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
public void actionPerformed(ActionEvent e) {
int m = (Integer.parseInt(text_m.getText())); //month
int d = (Integer.parseInt(text_d.getText())); //day
String my_sign = dochi(m, d);
text3.setText(my_sign);
System.out.println(my_sign + "--");
JFileChooser fileChooser = new JFileChooser();
File selectedFile = null;
int returnValue = fileChooser.showOpenDialog(null);
if (returnValue == JFileChooser.APPROVE_OPTION) {
selectedFile = fileChooser.getSelectedFile();
System.out.println(selectedFile.getName());
text_file.setText(selectedFile.getName());
}
FileReader fr = null;
try{
fr = new FileReader(selectedFile);
} catch (FileNotFoundException e1) {
e1.printStackTrace();
}
BufferedReader br = new BufferedReader(fr);
String line, tempstring;
String [] tempArray = new String [3];
ArrayList myList = new ArrayList();
String [] sign_List = new String [3];
int i = 0;
int count_sign = 0;
try {
while ((line = br.readLine()) != null) {
tempstring = line;
tempArray = tempstring.split("\\s");
for (i = 0; i < tempArray.length; i++){
myList.add(tempArray[i]);
//System.out.println(tempArray[i]+"==");
//System.out.println(myList+"--");
}
for (i = 0; i < tempArray.length/3; i = i + 3) {
if (i < 3) {
System.out.println(tempArray[1]);
System.out.println(tempArray[2]);
int m1 = Integer.parseInt(tempArray[1]);
int d1 = Integer.parseInt(tempArray[2]);
String other_sign = dochi(m1, d1);
//System.out.println(other_sign + "====");
sign_List[i] = other_sign;
System.out.println(sign_List[i] + "vvvv");
for (i = 0; i < sign_List.length; i++) {
if (sign_List[i] == my_sign){
count_sign += 1;
}
text4.setText(String.valueOf(count_sign));
}
}
}
}
} catch (IOException e1) { e1.printStackTrace(); }
}
public String dochi(int m, int d) {
int sign_case = 0;
if (m == 1 & (d >= 21 & d <= 31)) sign_case = 1;
if (m == 2 & (d >= 1 & d <= 19)) sign_case = 1;
if (m == 2 & (d >= 20 & d <= 29)) sign_case = 2;
if (m == 3 & (d >= 1 & d <= 20)) sign_case = 2;
if (m == 3 & (d >= 21 & d <= 31)) sign_case = 3;
if (m == 4 & (d >= 1 & d <= 20)) sign_case = 3;
if (m == 4 & (d >= 21 & d <= 30)) sign_case = 4;
if (m == 5 & (d >= 1 & d <= 21)) sign_case = 4;
if (m == 5 & (d >= 22 & d <= 31)) sign_case = 5;
if (m == 6 & (d >= 1 & d <= 21)) sign_case = 5;
if (m == 6 & (d >= 22 & d <= 30)) sign_case = 6;
if (m == 7 & (d >= 1 & d <= 23)) sign_case = 6;
if (m == 7 & (d >= 24 & d <= 31)) sign_case = 7;
if (m == 8 & (d >= 1 & d <= 23)) sign_case = 7;
if (m == 8 & (d >= 24 & d <= 31)) sign_case = 8;
if (m == 9 & (d >= 1 & d <= 23)) sign_case = 8;
if (m == 9 & (d >= 24 & d <= 30)) sign_case = 9;
if (m == 10 & (d >= 1 & d <= 23)) sign_case = 9;
if (m == 10 & (d >= 24 & d <= 31)) sign_case = 10;
if (m == 11 & (d >= 1 & d <= 22)) sign_case = 10;
if (m == 11 & (d >= 23 & d <= 30)) sign_case = 11;
if (m == 12 & (d >= 1 & d <= 22)) sign_case = 11;
if (m == 12 & (d >= 23 & d <= 31)) sign_case = 12;
if (m == 1 & (d >= 1 & d <= 22)) sign_case = 12;
String sign = "";
switch (sign_case){
case 1:
sign = "水瓶座"; break;
case 2:
sign = "雙魚座"; break;
case 3:
sign = "牡羊座"; break;
case 4:
sign = "金牛座"; break;
case 5:
sign = "雙子座"; break;
case 6:
sign = "巨蟹座"; break;
case 7:
sign = "獅子座"; break;
case 8:
sign = "處女座"; break;
case 9:
sign = "天枰座"; break;
case 10:
sign = "天蠍座"; break;
case 11:
sign = "射手座"; break;
case 12:
sign = "摩羯座"; break;
default:
sign = "???"; break;
}
return sign;
}
```
:::
---
# 2019-05-27 class
## ==[Java JFugue](http://www.jfugue.org/)==
* 安裝並使用：右鍵 -> Build Path - ==Configure Build Path...== -> Libraries - ==Add External JARs...== -> Apply and Close
* [The Complete Guide to JFugue](http://www.jfugue.org/4/jfbmrkklprpp/TheCompleteGuideToJFugue-v1.pdf)
:::warning
* Pitch相關
* 休止符：R
* 升記號：#
* 降記號：b
* 分部：V
* V0 … V1…
* 樂器：I
* I[Piano]… I[Flute]…
* Duration相關
* 四拍：w (或qqqq)
* 二拍：h (或qq)
* 一拍：q
* 半拍：i
* 四分之一拍：s
* 八分之一拍：t
* 16分之一拍：x
* 32分之一拍：o
* 附點：.
:::
:::success
### HW10：Audio練習
```java=
import org.jfugue.player.Player;
public class HelloWorld {
public static void main(String[] args) {
Player player = new Player();
player.play("C D E F G A B");
}
}
```
```java=
import org.jfugue.player.Player;
import org.jfugue.pattern.Pattern;
public class Audio {
public static void main(String[] args) {
/*
Pattern p1 = new Pattern("Eq Ch. | Dq Eq Dq Cq"
).setVoice(0).setInstrument("Piano");
Pattern p2 = new Pattern("Rw | GmajQ CmajQ"
).setVoice(1).setInstrument("Flute");
*/
Pattern p1 = new Pattern("V0 I[Piano] Eq Ch. | Dq Eq Dq Cq");
Pattern p2 = new Pattern("V1 I[Flute] Rw | GmajQ CmajQ");
Player player = new Player();
player.play(p1, p2);
}
}
```
:::
---
# 2019-06-03 class
## ==Java JFugue (記憶遊戲)==
```java=
import java.util.Scanner;
import org.jfugue.player.Player;
public class audio {
public static void main(String[] args) {
Player player = new Player();
Scanner sc = new Scanner(System.in);
String q = "R "; // question
String a = "R "; // answer
int note;
boolean more = true;
while (more) {
note = (int)(Math.random()*8);
switch (note) {
case 0:
q += " C4"; break;
case 1:
q += " D4"; break;
case 2:
q += " E4"; break;
case 3:
q += " F4"; break;
case 4:
q += " G4"; break;
case 5:
q += " A4"; break;
case 6:
q += " B4"; break;
case 7:
q += " C5"; break;
default:
System.out.println("Error!");
}
System.out.println(q);
player.play(q);
int dummy = sc.nextInt(); //User input their answer.
}
}
}
Output:
R G4
1
R G4 B4
2
R G4 B4 D4
1
R G4 B4 D4 F4
...
```
:::info
* [取出字串中的字元：str.charAt(0);](https://blog.csdn.net/ammmd/article/details/3014251)
```
String str = "abc";
char ch = str.charAt(0); //ch = a
char ch2 = str.charAt(1); //ch2 = b
```
* [使用Scanner，讀取字串 (==nextLine()== vs. ==next()==)](http://www.runoob.com/java/java-scanner-class.html)
```java=
import java.util.Scanner;
public class ttt {
public static void main(String[] args) {
String str1, str2;
Scanner sc = new Scanner(System.in);
System.out.print("請輸入一字串：");
str1 = sc.nextLine();
System.out.println("您輸入的字串一為：\n" + str1 );
System.out.println("----------------");
System.out.print("請輸入一字串(不含空白字元、空白鍵、Tab)：");
str2 = sc.next();
System.out.println("您輸入的字串一為：\n" + str2 );
}
}
Output:
請輸入一字串：hell ooo
您輸入的字串一為：
hell ooo
----------------
請輸入一字串(不含空白字元、空白鍵、Tab)：hell ooo
您輸入的字串一為：
hell
```
* 讀取檔案中的內容：==br.readLine()==
```java=
import java.io.*;
public class StringReaderDemo {
public static void main(String[] args) {
String s = "Hello World";
StringReader sr = new StringReader(s);
try {
for (int i = 0; i < 5; i++) {
char c = (char) sr.read();
System.out.print("" + c);
}
sr.close();
} catch (IOException ex) { ex.printStackTrace(); }
}
}
```
:::
:::success
### HW 11：音感記憶遊戲
```java=
import java.util.*;
import org.jfugue.player.Player;
public class audio {
public static void main(String[] args) {
Player player = new Player();
Scanner sc = new Scanner(System.in);
System.out.println(" --- 絕對音感 + 記憶遊戲 --- ");
/*
String song = "V0 I[Flute] Ci Di Ei Fi Gq Ai Fi Ei Ri Di Ri Ch ";
song += "V1 I[Music_Box] CmajQQQ FmajQ CmajQ RQ CmajQQ";
player.play(song);
*/
String q = "R ";
String a = "R ";
int note;
boolean more = true;
while (more) {
note = (int)(Math.random()*8);
switch (note) {
case 0:
q += " C4"; break;
case 1:
q += " D4"; break;
case 2:
q += " E4"; break;
case 3:
q += " F4"; break;
case 4:
q += " G4"; break;
case 5:
q += " A4"; break;
case 6:
q += " B4"; break;
case 7:
q += " C5"; break;
default:
System.out.println("Error!");
}
System.out.println(q);
player.play(q);
int dummy = sc.nextInt();
switch (dummy) {
case 0:
a += " C4"; break;
case 1:
a += " D4"; break;
case 2:
a += " E4"; break;
case 3:
a += " F4"; break;
case 4:
a += " G4"; break;
case 5:
a += " A4"; break;
case 6:
a += " B4"; break;
case 7:
a += " C5"; break;
default:
System.out.println("Error!");
}
if (q.equals(a)) {
System.out.println("identical !");
}
else {
System.out.println("not same");
System.out.println("遊戲結束");
break;
}
}
}
}
Output:
--- 絕對音感 + 記憶遊戲 ---
R D4
1
identical !
R D4 B4
6
identical !
R D4 B4 B4
6
identical !
R D4 B4 B4 F4
8
Error!
not same
遊戲結束
```
:::
---
# 2019-06-10 class
## 預備環境：`XAMPP` & `Connector/J`
* [安裝 XAMPP](https://www.apachefriends.org/zh_tw/index.html)：Apache + MariaDB + PHP + Perl
`xampp-windows-x64-7.3.6-0-VC15-installer.exe`
* Apache：網頁伺服器
* MySQL：資料庫
* phpmyadmin
* [下載 Connector/J](https://dev.mysql.com/downloads/connector/j/5.1.html)： `mysql-connector-java-5.1.47-bin.jar`
## ==Eclipse 設定 JDBC 連接 MySQL資料庫==
* 安裝並使用：右鍵 -> Build Path - ==Configure Build Path...== -> Libraries - ==Add External JARs...== - `【mysql-connector-java-5.1.47-bin.jar】` -> Apply and Close
* 建構式：直接執行與現在.java名稱相同的部分。
:::success
### HW12：JDBC連接MySQL練習
```java=
package db;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class jdbcmysql {
private Connection con = null; //Database objects
//連接object
private Statement stat = null;
//執行,傳入之sql為完整字串
private ResultSet rs = null;
//結果集
private PreparedStatement pst = null;
//執行,傳入之sql為預儲之字申,需要傳入變數之位置
//先利用?來做標示
private String dropdbSQL = "DROP TABLE User ";
private String createdbSQL = "CREATE TABLE User ( id INTEGER," +
" name VARCHAR(20) , passwd VARCHAR(20))";
private String insertdbSQL = "insert into User(id,name,passwd)" +
"select ifNULL(max(id),0)+1,?,? FROM User";
private String selectSQL = "select * from User ";
public jdbcmysql() {
try {
Class.forName("com.mysql.jdbc.Driver");
//註冊driver
con = DriverManager.getConnection(
"jdbc:mysql://localhost/test?useUnicode=true&characterEncoding=Big5",
"root","");
//取得connection
//jdbc:mysql://localhost/test?useUnicode=true&characterEncoding=Big5
//localhost是主機名,test是database名
//useUnicode=true&characterEncoding=Big5使用的編碼
} catch(ClassNotFoundException e) {
System.out.println("DriverClassNotFound :"+e.toString());
} catch(SQLException x) {
System.out.println("Exception :"+x.toString());
}
}
//建立table的方式
//可以看看Statement的使用方式
public void createTable() {
try {
stat = con.createStatement();
stat.executeUpdate(createdbSQL);
} catch(SQLException e) {
System.out.println("CreateDB Exception :" + e.toString());
} finally {
Close();
}
}
//新增資料
//可以看看PrepareStatement的使用方式
public void insertTable( String name,String passwd) {
try {
pst = con.prepareStatement(insertdbSQL);
pst.setString(1, name);
pst.setString(2, passwd);
pst.executeUpdate();
} catch(SQLException e) {
System.out.println("InsertDB Exception :" + e.toString());
} finally {
Close();
}
}
//刪除Table,
//跟建立table很像
public void dropTable() {
try {
stat = con.createStatement();
stat.executeUpdate(dropdbSQL);
} catch(SQLException e) {
System.out.println("DropDB Exception :" + e.toString());
} finally {
Close();
}
}
//查詢資料
//可以看看回傳結果集及取得資料方式
public void SelectTable() {
try {
stat = con.createStatement();
rs = stat.executeQuery(selectSQL);
System.out.println("ID\t\tName\t\tPASSWORD");
while(rs.next()) {
System.out.println(rs.getInt("id")+"\t\t"+
rs.getString("name")+"\t\t"+
rs.getString("passwd"));
}
} catch(SQLException e) {
System.out.println("DropDB Exception :" + e.toString());
} finally {
Close();
}
}
//完整使用完資料庫後,記得要關閉所有Object
//否則在等待Timeout時,可能會有Connection poor的狀況
private void Close() {
try {
if(rs!=null) {
rs.close();
rs = null;
}
if(stat!=null) {
stat.close();
stat = null;
}
if(pst!=null) {
pst.close();
pst = null;
}
} catch(SQLException e) {
System.out.println("Close Exception :" + e.toString());
}
}
public static void main(String[] args) {
//測看看是否正常
jdbcmysql test = new jdbcmysql();
test.dropTable();
test.createTable();
test.insertTable("yku", "12356");
test.insertTable("yku2", "7890");
test.SelectTable();
}
}
Output:
ID Name PASSWORD
1 yku 12356
2 yku2 7890
```
:::
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