Logback configuration error detected

原因: spring-boot-starter-web包的时候他里面默认使用了logback日志,这样就会产生日志包的冲突,其实不只是starter-web包默认引入的logback还有很多的包默认引入的logback包

解决: 需要把 spring-boot-starter-web 放到pom文件中依赖的第一位,在向下执行的时候也会排除所有的默认logger了 。

A generic error occurred in GDI+

  1. 因为 .net GDI+ 是对底层 的封装。 所以可以尝试用 Marshal.GetLastWin32Error();函数获得底层错误代码
try{
   image.Save(filename, System.Drawing.Imaging.ImageFormat.Png);
} 
catch (Exception exp)
            {
                var code = Marshal.GetLastWin32Error();
                throw new Exception(exp.Message + ":" + code.ToString(), exp);
            }

2. 查看错误代码含义

ERROR_PATH_NOT_FOUND

3 (0x3)

The system cannot find the path specified.

原因:save的目录不存在。解决:手动或通过程序建save的目录。

ERROR_ACCESS_DENIED

5 (0x5)

Access is denied.

原因: save的目录没有权限

解决: 查看目录的权限

ERROR_SHARING_VIOLATION32 (0x20)

The process cannot access the file because it is being used by another process.

原因:

  从一个文件构造的Bitmap 对象或一个 Image 对象, 在该对象的生存期内该文件处于锁定状态。 因此, 在没有释放这个Image或Bitmap对象前,无法更改图像并将其保存回原文件。

  解决方法:

解决:

构造一个新的Image对象,然后把原来的Image对象中的图象通过Graphics的DrawImage()方法,拷贝到新Image对象中,最后通过Dispose()方法释放原来的Image对象:

  Image image = new Bitmap ( openFileDialog1 . FileName );

  //新建第二个Image类型的变量newImage,这里是根据程序需要设置自己设置。

  Image newImage = new Bitmap ( 800 , 600 );

  //将第一个bmp拷贝到bmp2中

  Graphics draw = Graphics . FromImage ( newImage);

  draw . DrawImage ( image , 0 , 0 );

  //释放第一个Image对象

  image.Dispose();

 3.其他问题

a.  Image 对应的Stream被Dispose了。

b.  保存成png时报错。

转载自` https://www.cnblogs.com/guangfengli/p/5920104.html `

maven发布的项目打包jsp

从eslipse迁移的Web项目的jsp、js、css等文件都是放到WebContent里,而Maven中,这些文件是放到webapp下的。所以,如果你直接用Maven进行install也就是打包的时候,你的页面相关的文件不会被打包进去,你会发现打好的war包里只有src下的.class文件和一些配置文件。那么如何将页面等文件也包含进去呢?

<build>
	<finalName>projectName</finalName>
	<plugins>
		<plugin>
			<groupId>org.apache.maven.plugins</groupId>
			<artifactId>maven-war-plugin</artifactId>
			<version>3.2.3</version>					
			<configuration>
				<!--指定web.xml文件的位置-->
				<webXml>WebContent/WEB-INF/web.xml</webXml>				
				<!--指定jsp等文件所在位置-->   
				<warSourceDirectory>WebContent</warSourceDirectory>
			</configuration>
		</plugin>
	</plugins>
</build>

批量 修改 数据库的字符集和排序规则

-- 字符集为utf8mb4,排序规则为utf8mb4_unicode_ci

-- 修改数据库
ALTER DATABASE 数据库名 CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

-- 设置每张表的字符集和排序规则为为 utf8mb4、utf8mb4_unicode_ci
SELECT CONCAT('ALTER TABLE ', table_name, ' CONVERT TO CHARACTER SET  utf8mb4 COLLATE utf8mb4_unicode_ci;')
FROM information_schema.TABLES
WHERE TABLE_SCHEMA = '数据库名';

-- 批量修改字符编码和排序编码
select concat('ALTER TABLE `', table_name, '` MODIFY `', column_name, '`', DATA_TYPE, '(', CHARACTER_MAXIMUM_LENGTH,
              ') CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci', ';')
FROM information_schema.COLUMNS
WHERE table_schema = '数据库名'
  AND DATA_TYPE IN ('varchar' ,'char');

validatorUtil 工具类校验fastjson转对象的参数

  1. 工具类
import org.hibernate.validator.HibernateValidator;

import javax.validation.ConstraintViolation;
import javax.validation.Validator;

import javax.validation.Validation;
import java.util.Set;

public class ValidatorUtil {
    /**
     * 开启快速结束模式 failFast (true)
     */
    private static final Validator validator = Validation.byProvider(HibernateValidator.class).configure().failFast(false).buildValidatorFactory().getValidator();

    /**
     * 校验对象
     *
     * @param t bean
     * @param groups 校验组
     * @return ValidResult
     */
    public static <T> ValidResult validateBean(T t, Class<?>...groups) {
        ValidResult result = new ValidResult();
        Set<ConstraintViolation<T>> violationSet = validator.validate(t,groups);
        boolean hasError = violationSet != null && violationSet.size() > 0;
        result.setHasErrors(hasError);
        if (hasError) {
            for (ConstraintViolation<T> violation : violationSet) {
                result.addError(violation.getPropertyPath().toString(), violation.getMessage());
            }
        }
        return result;
    }
    /**
     * 校验bean的某一个属性
     *
     * @param obj          bean
     * @param propertyName 属性名称
     * @return ValidResult
     */
    public static <T> ValidResult validateProperty(T obj, String propertyName) {
        ValidResult result = new ValidResult();
        Set<ConstraintViolation<T>> violationSet = validator.validateProperty(obj, propertyName);
        boolean hasError = violationSet != null && violationSet.size() > 0;
        result.setHasErrors(hasError);
        if (hasError) {
            for (ConstraintViolation<T> violation : violationSet) {
                result.addError(propertyName, violation.getMessage());
            }
        }
        return result;
    }
}

2. ValidResult 校验结果类

import java.util.ArrayList;
import java.util.List;

public class ValidResult {

    /**
     * 是否有错误
     */
    private boolean hasErrors;

    /**
     * 错误信息
     */
    private final List<ValidErrorMessage> errors;

    public ValidResult() {
        this.errors = new ArrayList<>();
    }
    public boolean hasErrors() {
        return hasErrors;
    }

    public void setHasErrors(boolean hasErrors) {
        this.hasErrors = hasErrors;
    }

    /**
     * 获取所有验证信息
     * @return 集合形式
     */
    public List<ValidErrorMessage> getAllErrors() {
        return errors;
    }
    /**
     * 获取所有验证信息
     * @return 字符串形式
     */
    public String getErrors(){
        StringBuilder sb = new StringBuilder();
        for (ValidErrorMessage error : errors) {
            sb.append(error.getPropertyPath()).append(":").append(error.getMessage()).append(" ");
        }
        return sb.toString();
    }

    public void addError(String propertyName, String message) {
        this.errors.add(new ValidErrorMessage(propertyName, message));
    }
}

3. 错误类

public class ValidErrorMessage {
    private String propertyPath;

    private String message;

    public String getPropertyPath() {
        return propertyPath;
    }

    public void setPropertyPath(String propertyPath) {
        this.propertyPath = propertyPath;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    public ValidErrorMessage() {
    }

    public ValidErrorMessage(String propertyPath, String message) {
        this.propertyPath = propertyPath;
        this.message = message;
    }
}

4. 校验类

import javax.validation.constraints.NotBlank;
import javax.validation.constraints.NotEmpty;

public class CheckDataUpdateTimeJson {
    @NotBlank(message = "token不能为空!")
    private String token;
    
    public void setToken(String token) {
        this.token = token;
    }
    public String getToken() {
        return token;
    }
}

5. 使用

String requestJson = HelperUtils.convertStreamToString(request.getInputStream());
            CheckDataUpdateTimeJson paramJson = JSON.parseObject(requestJson, CheckDataUpdateTimeJson.class);
            ValidResult validResult = ValidatorUtil.validateBean(paramJson);
            if (validResult.hasErrors()) {
                System.out.println(validResult.getErrors());
            }

Spring 添加 Hibernate Validator支持 Add a provider like Hibernate Validator (RI) to your classpath

  1. 添加依赖
<dependency>
            <groupId>org.hibernate.validator</groupId>
            <artifactId>hibernate-validator</artifactId>
            <version>6.1.2.Final</version>
        </dependency>
<dependency>
            <groupId>javax.validation</groupId>
            <artifactId>validation-api</artifactId>
            <version>2.0.1.Final</version>
        </dependency>
<dependency>
            <groupId>org.hibernate.validator</groupId>
            <artifactId>hibernate-validator-annotation-processor</artifactId>
            <version>6.1.0.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate.validator</groupId>
            <artifactId>hibernate-validator-cdi</artifactId>
            <version>6.1.2.Final</version>
        </dependency>
<dependency>
            <groupId>jakarta.validation</groupId>
            <artifactId>jakarta.validation-api</artifactId>
            <version>2.0.2</version>
        </dependency>
<dependency>
            <groupId>org.jboss.logging</groupId>
            <artifactId>jboss-logging</artifactId>
            <version>3.4.1.Final</version>
        </dependency>
<dependency>
            <groupId>org.glassfish</groupId>
            <artifactId>jakarta.el</artifactId>
            <version>3.0.3</version>
        </dependency>
<dependency>
            <groupId>javax</groupId>
            <artifactId>javaee-api</artifactId>
            <version>8.0.1</version>
            <scope>provided</scope>
        </dependency>

2. 向容器里注册一个处理器:

@Configuration
@EnableWebMvc
public class WebRootConfig {

    @Bean
    public MethodValidationPostProcessor methodValidationPostProcessor() {
        return new MethodValidationPostProcessor();
    }
}

3. 增加验证类

public class AppLoginParam {
    @NotNull(message = "userName不能为空")
    private String userName;
    @NotNull(message = "password不能为空")
    private String password;
    
    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }
}

4. Controller增加验证

    @RequestMapping("/login")
    @ResponseBody
    public AjaxJson login(@Valid @RequestBody AppLoginParam requestParam, BindingResult bindingResult) {
        AjaxJson res = new AjaxJson();
        Integer code = response.getStatus();
        res.setCode(String.valueOf(code));
        res.setStatus(false);
        // validator 验证
        if (bindingResult.hasErrors()) {
            res.setMessage(bindingResult.getFieldError().getDefaultMessage());
            return res;
        }
// do something....
}

cannot read realtime clock: Invalid argument

wsl ubuntu 20.04出现此问题

解决方法:

sudo -i
sudo mv /bin/sleep /bin/sleep~ ; touch /bin/sleep ; chmod +x /bin/sleep

或者:
wget https://launchpad.net/~rafaeldtinoco/+archive/ubuntu/lp1871129/+files/libc6_2.31-0ubuntu8+lp1871129~1_amd64.deb
sudo dpkg --install libc6_2.31-0ubuntu8+lp1871129~1_amd64.deb
sudo apt-mark hold libc6
sudo apt --fix-broken install
sudo apt full-upgrade