for(i=1;i=4;i++)
創(chuàng)新互聯(lián)建站專業(yè)為企業(yè)提供桃山網(wǎng)站建設(shè)、桃山做網(wǎng)站、桃山網(wǎng)站設(shè)計、桃山網(wǎng)站制作等企業(yè)網(wǎng)站建設(shè)、網(wǎng)頁設(shè)計與制作、桃山企業(yè)網(wǎng)站模板建站服務(wù),十余年桃山做網(wǎng)站經(jīng)驗,不只是建網(wǎng)站,更提供有價值的思路和整體網(wǎng)絡(luò)服務(wù)。
{
這個小的for是打印每一行前邊的空格
for(j=1;j=4-i;j++)
System.out.print(" ");
這個是打印星星的
for(j=1;j=2*i-1;j++)
System.out.print("*");
這個是打印完一行的換行
System.out.println("");
}
下邊的是一樣的 ?只不過每一行的空格和星星數(shù) ? 和上邊是翻過來的
for(i=1;i=3;i++)
{
for(j=1;j=i;j++)
System.out.print(" ");
for(j=1;j=7-2*i;j++)
System.out.print("*");
System.out.println("");
}
java.sql.SQLException: 無效的列索引
無效的列索引
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:111)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:145)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:207)
atoracle.jdbc.driver.OraclePreparedStatement.setStringInternal(OraclePreparedStatement.java:5328)
atoracle.jdbc.driver.OraclePreparedStatement.setString(OraclePreparedStatement.java:5320)
at untitled5.addreader1.validID(addreader1.java:128)
at untitled5.addreader1.jButton1_actionPerformed(addreader1.java:97)
at untitled5.addreader1_jButton1_actionAdapter.actionPerformed(addreader1.java:175)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
代碼:String driverName = "oracle.jdbc.OracleDriver";
Driver driver = (Driver) Class.forName(driverName).newInstance();
//連接數(shù)據(jù)庫
Connection con = DriverManager.getConnection(
"jdbc:oracle:thin:@LONG:1521:orcl", "sysman", "tongfang");
PreparedStatement pstmt = con.prepareStatement(
" insert into reader values(?)");
pstmt.setString(1, str1);
pstmt.setString(2,str2);
pstmt.setString(3,str3);
pstmt.setString(4,str4);
ResultSet res = pstmt.executeQuery();
java打印菱形方法:
package?circulationDemo;
import?java.util.Scanner;
public?class?Test?{
public?static?void?main(String[]?args)?{
Scanner?input?=?new?Scanner(System.in);
System.out.println("請輸入要打印的行數(shù):");
int?num?=?input.nextInt();
t1(num);//?正直角
split();
t2(num);//?倒直角
split();
t3(num);//?等腰三角
split();
t4(num);//?等腰倒三角++
split();
t5(num);//?等腰倒三角--
split();
t6(num);//?實心菱形
split();
t7(num);//?空心菱形(1)
split();
t8(num);//?空心菱形(2)
split();
t9(num);//?空心菱形(3)
}
private?static?void?t9(int?num)?{
for?(int?k?=?1;?k?=?num;?k++)?{
for?(int?i?=?1;?i?=?(num?-?k);?i++)?{
System.out.print("?");
}
System.out.print("*");
for?(int?i?=?1;?i?=?((k?-?2)?*?2?+?1);?i++)?{
System.out.print("?");
}
if?(k?!=?1)?{
System.out.print("*");
}
System.out.println();
}
for?(int?k?=?num-1;?k?=?1;?k--)?{
for?(int?i?=?1;?i?=?(num?-?k);?i++)?{
System.out.print("?");
}
System.out.print("*");
for?(int?i?=?1;?i?=?((k?-?2)?*?2?+?1);?i++)?{
System.out.print("?");
}
if?(k?!=?1)?{
System.out.print("*");
}
System.out.println();
}
}
private?static?void?t8(int?num)?{
//?上半部分
for?(int?i?=?1;?i?=?num;?i++)?{
//?打印上半部分空格
for?(int?j?=?1;?j?=?num?-?i;?j++)?{
System.out.print("?");
}
//?打印原本實心的*部分
for?(int?j?=?1;?j?=?2?*?i?-?1;?j++)?{
//?僅在一行的開頭和末尾打印*
if?(j?==?1?||?j?==?2?*?i?-?1)?{
System.out.print("*");
}?else?{
System.out.print("?");
}
}
System.out.println();
}
//?下半部分
for?(int?i?=?1;?i?=?num?-?1;?i++)?{
for?(int?j?=?1;?j?=?i;?j++)?{
System.out.print("?");
}
for?(int?j?=?1;?j?=?2?*?(num?-?i?-?1)?+?1;?j++)?{
if?(j?==?1?||?j?==?2?*?(num?-?i?-?1)?+?1)?{
System.out.print("*");
}?else?{
System.out.print("?");
}
}
System.out.println();
}
}
private?static?void?t7(int?num)?{
//?打印上半部分
for?(int?i?=?1;?i?=?num;?i++)?{
//?打印空格
for?(int?j?=?1;?j?=?(num?-?i);?j++)?{
System.out.print("?");
}
//?打印*的個數(shù)
if?(i?==?1)?{
System.out.print("*");
}?else?{
System.out.print("*");
//?打印菱形里的空格
for?(int?j?=?1;?j?=?(2?*?i?-?3);?j++)?{
System.out.print("?");
}
System.out.print("*");
}
System.out.println();
}
//?打印下半部分
for?(int?i?=?num?-?1;?i??0;?i--)?{
//?打印空格
for?(int?j?=?1;?j?=?(num?-?i);?j++)?{
System.out.print("?");
}
//?打印*的個數(shù)
if?(i?==?1)?{
System.out.print("*");
}?else?{
System.out.print("*");
//?打印菱形里的空格
for?(int?j?=?1;?j?=?(2?*?i?-?3);?j++)?{
System.out.print("?");
}
System.out.print("*");
}
System.out.println();
}
}
private?static?void?t6(int?num)?{
//?上半部分
for?(int?i?=?1;?i?=?num;?i++)?{
for?(int?j?=?1;?j?=?num?-?i;?j++)?{
System.out.print("?");
}
for?(int?j?=?1;?j?=?2?*?i?-?1;?j++)?{
System.out.print("*");
}
System.out.println();
}
//?下半部分
for?(int?i?=?1;?i?=?num?-?1;?i++)?{
for?(int?j?=?1;?j?=?i;?j++)?{
System.out.print("?");
}
for?(int?j?=?1;?j?=?2?*?(num?-?1?-?i)?+?1;?j++)?{
System.out.print("*");
}
System.out.println();
}
}
private?static?void?t5(int?num)?{
for?(int?i?=?num;?i??0;?i--)?{
for?(int?j?=?1;?j?=?num?-?i;?j++)?{
System.out.print("?");
}
for?(int?j?=?1;?j?=?2?*?i?-?1;?j++)?{
System.out.print("*");
}
System.out.println();
}
回答于?2022-12-14
Java利用for循環(huán)輸出空心菱形的實例代碼
編寫程序,在控制臺上輸出空心菱形,對角距離為6.
代碼如下:
public class Diamond {
public static void main(String[] args) {
printHollowRhombus(6);
}
public static void printHollowRhombus(int size) {
if (size % 2 == 0) {
size++;// 計算菱形大小
}
for (int i = 0; i size / 2 + 1; i++) {
for (int j = size / 2 + 1; j i + 1; j--) {
System.out.print("? ");// 輸出左上角位置的空白
}
for (int j = 0; j 2 * i + 1; j++) {
if (j == 0 || j == 2 * i) {
System.out.print("* ");// 輸出菱形上半部邊緣
} else {
System.out.print("? ");// 輸出菱形上半部空心
}
}
System.out.println("");???? //換行
}
for (int i = size / 2 + 1; i size; i++) {
for (int j = 0; j i - size / 2; j++) {
System.out.print("? ");// 輸出菱形左下角空白
}
for (int j = 0; j 2 * size - 1 - 2 * i; j++) {
if (j == 0 || j == 2 * (size - i - 1)) {
System.out.print("* ");// 輸出菱形下半部邊緣
} else {
System.out.print("? ");// 輸出菱形下半部空心
}
}
System.out.println("");???? //換行
}
}
}
效果如圖: