代码报错?????
package com.imooc.test;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.HashMap;
import java.util.Map;
public class Demo {
Connection conn=null;
public static void main(String[] args) {
//运行之前需要创建数据库和表,参考test.sql文件
Demo d= new Demo();
Map param=new HashMap();
param.put("id",5);
param.put("name","amy");
param.put("password","123456");
d.insert(param);
d.getAll();
d.close();
}
public void createDb() {
String url="jdbc:mysql:///test1?useSSL=false&useUnicode=true&characterEncoding=UTF8&serverTimezone=GMT%2B8";
String name="com.mysql.cj.jdbc.Driver";
String user="root";
String password="1234";
try {
Class.forName(name);//指定连接类型
conn=DriverManager.getConnection(url,user,password);
//pst=conn.preparedStatement(sql);//准备执行语句
}catch(Exception e) {
e.printStackTrace();
}
}
public int insert(Map param) {
this.createDb();
int i=0;
String sql="INSERT INTO user(id,username,password) VALUSE(?,?,?)";
PreparedStatement pstmt=null;
try {
pstmt=this.conn.prepareStatement(sql);
pstmt.setString(1, (String)param.get("id"));
pstmt.setString(2, (String)param.get("name"));
pstmt.setString(3, (String)param.get("password"));
i=pstmt.executeUpdate();
pstmt.close();
}catch(Exception e) {
e.printStackTrace();
}
return i;
}
public void getAll() {
String sql="select * form user";
PreparedStatement pstmt=null;
try {
pstmt=this.conn.prepareStatement(sql);
ResultSet rs=pstmt.executeQuery();
int col=rs.getMetaData().getColumnCount();
System.out.println("=========================");
while(rs.next()) {
for(int i=1;i<=col;i++) {
System.out.print(rs.getString(i)+"\t");
if((i==2)&&(rs.getString(i).length()<8)) {
System.out.println("\t");
}
}
System.out.println("");
}
System.out.println("=========================");
}catch(Exception e) {
e.printStackTrace();
}
}
public void close() {
}
}**********************************************************
package com.imooc.test;
import static org.junit.Assert.*;
import java.util.HashMap;
import java.util.Map;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
public class DemoTest1 {
public static Demo d= new Demo();
@Before
public void setUp() throws Exception {
}
@Before
public void testCreateDb() {
d.createDb();
}
@Test
public void testInsert() {
Map param=new HashMap();
param.put("id",6);
param.put("name","larry");
param.put("password","123456");
d.insert(param);
}
@Test
public void testGetAll() {
d.getAll();
}
@After
public void testClose() {
d.close();
}
}报错信息????????????
java.sql.SQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'form user' at line 1
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:118)
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:95)
at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122)
at com.mysql.cj.jdbc.ClientPreparedStatement.executeInternal(ClientPreparedStatement.java:960)
at com.mysql.cj.jdbc.ClientPreparedStatement.executeQuery(ClientPreparedStatement.java:1019)
at com.imooc.test.Demo.getAll(Demo.java:61)
at com.imooc.test.DemoTest1.testGetAll(DemoTest1.java:34)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:89)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:41)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:541)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:763)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:463)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:209)
java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.String
at com.imooc.test.Demo.insert(Demo.java:44)
at com.imooc.test.DemoTest1.testInsert(DemoTest1.java:29)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:89)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:41)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:541)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:763)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:463)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:209)
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报错信息?
java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.String
at com.imooc.test.Demo.insert(Demo.java:44)
at com.imooc.test.Demo.main(Demo.java:19)
java.sql.SQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'form user' at line 1
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:118)
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:95)
at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122)
at com.mysql.cj.jdbc.ClientPreparedStatement.executeInternal(ClientPreparedStatement.java:960)
at com.mysql.cj.jdbc.ClientPreparedStatement.executeQuery(ClientPreparedStatement.java:1019)
at com.imooc.test.Demo.getAll(Demo.java:61)
at com.imooc.test.Demo.main(Demo.java:20)
package com.imooc.test;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.HashMap;
import java.util.Map;
public class Demo {
Connection conn=null;
public static void main(String[] args) {
//运行之前需要创建数据库和表,参考test.sql文件
Demo d= new Demo();
Map param=new HashMap();
param.put("id",5);
param.put("name","amy");
param.put("password","123456");
d.insert(param);
d.getAll();
d.close();
}
public void createDb() {
String url="jdbc:mysql:///test1?useSSL=false&useUnicode=true&characterEncoding=UTF8&serverTimezone=GMT%2B8";
String name="com.mysql.cj.jdbc.Driver";
String user="root";
String password="1234";
try {
Class.forName(name);//指定连接类型
conn=DriverManager.getConnection(url,user,password);
//pst=conn.preparedStatement(sql);//准备执行语句
}catch(Exception e) {
e.printStackTrace();
}
}
public int insert(Map param) {
this.createDb();
int i=0;
String sql="INSERT INTO user(id,username,password) VALUSE(?,?,?)";
PreparedStatement pstmt=null;
try {
pstmt=this.conn.prepareStatement(sql);
pstmt.setString(1, (String)param.get("id"));
pstmt.setString(2, (String)param.get("name"));
pstmt.setString(3, (String)param.get("password"));
i=pstmt.executeUpdate();
pstmt.close();
}catch(Exception e) {
e.printStackTrace();
}
return i;
}
public void getAll() {
String sql="select * form user";
PreparedStatement pstmt=null;
try {
pstmt=this.conn.prepareStatement(sql);
ResultSet rs=pstmt.executeQuery();
int col=rs.getMetaData().getColumnCount();
System.out.println("=========================");
while(rs.next()) {
for(int i=1;i<=col;i++) {
System.out.print(rs.getString(i)+"\t");
if((i==2)&&(rs.getString(i).length()<8)) {
System.out.println("\t");
}
}
System.out.println("");
}
System.out.println("=========================");
}catch(Exception e) {
e.printStackTrace();
}
}
public void close() {
}
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