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() { } }
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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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