Programming Issues

Issues

Invalid initialDelayString cannot parse into long

Spring boot provides good support for the creation of spring boot schedulers. Schedulers are the tasks that run periodically at a specific interval. As soon as the application starts, these schedulers will run. Spring boot allows these schedulers to be started after a certain delay period. This delay is configured

Invalid fixedDelayString cannot parse into long

The scheduler interval is configured in milliseconds in spring boot application. The duration is a long value defined in @Scheduler configuration in fixedDelay variables. You can configure these values as a string parameter. If any error occurred when the string was converted to long, this exception will be thrown from

Unexpected error occurred in scheduled task

Schedulers in spring boot framework runs the configured the task method periodically. If any error occurred in the task method, the unexpected error exception is thrown by the spring boot. This is due to the logical issue in the code. Exception 2019-10-10 12:14:00.007 ERROR 49298 --- [ scheduling-1] o.s.s.s.TaskUtils$LoggingErrorHandler :

Encountered invalid Scheduled method input string

In spring boot framework, schedulers can be configured using cron jobs. If there are any issues related to cron job expression, Scheduler can not define the scheduled time frame. In this scenario, the scheduler will throw an input error and will not start the scheduler. Exception 2019-10-10 12:03:16.181 ERROR 48515

Invalid fixedRateString cannot parse into long

The scheduler interval is configured in milliseconds in spring boot application. The duration is a long value defined in @Scheduler configuration in fixedRate and fixedDelay variables. You can configure these values as a string parameter. If any error occurred when the string was converted to long, this exception will be

o.s.boot.SpringApplication: Application run failed, java.lang.IllegalArgumentException: null – @Scheduled Method

The spring boot @Scheduled method is not working and throws Application run failed, java.lang.IllegalArgumentException: null exception if the scheduler is configured with an invalid value in the @Scheduled annotation. The @Scheduled annotation is configured for two arguments, fixedRate and fixedDelay. If the argument is set to an invalid value, the

Encountered invalid @Scheduled method ‘task’: Exactly one of the ‘cron’, ‘fixedDelay(String)’, or ‘fixedRate(String)’ attributes is required

The exception “Encountered invalid @Scheduled method ‘task’: Exactly one of the ‘cron’, ‘fixedDelay(String)’, or ‘fixedRate(String)’ attributes is required” is thrown due to error while loading the scheduler bean at the startup of the spring boot application. Spring boot application allows scheduler to run on a regular basis. If spring boot does not load bean due to the configuration of the scheduler then

restartedMain Unresolved compilation problem

Spring boot application loads all the beans using bean factory. If any error occurred while invoking the java classes, this exception is thrown Exception Exception in thread "restartedMain" java.lang.reflect.InvocationTargetException at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.base/java.lang.reflect.Method.invoke(Unknown Source) at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) Caused by: java.lang.Error: Unresolved compilation problem: SpringApplication

Unable to open JDBC Connection for DDL execution

The spring boot application creates database connection in startup. The EntityManager class is responsible for basic CRUD database operation. If the creation of EntityManger is failed, then this error is shown Exception 2019-10-07 13:46:48.751 ERROR 5068 --- [ restartedMain] o.s.boot.SpringApplication : Application run failed org.springframework.beans.factory.BeanCreationException: Error creating bean with name

HikariPool-1 – Exception during pool initialization. java.sql.SQLSyntaxErrorException: Access denied for user ‘root’@’localhost’ to database

The exception “java.sql.SQLSyntaxErrorException: Access denied for user ‘root’@’localhost’ to database ‘testdb’” is thrown if you are using mysql database first time or newly installed. If you start the spring boot application, the jpa will try to create a database conection pool. If any error is thrown from the database, this

Failed to configure a DataSource: ‘url’ attribute is not specified and no embedded datasource could be configured.

The spring boot exception Failed to configure a DataSource: ‘url’ attribute is not specified and no embedded datasource could be configured. Reason: Failed to determine a suitable driver class occurs when the datasource url is not configured in the application.properties. If the spring-boot-starter-data-jpa dependency is configured in the spring boot

CONDITION EVALUATION DELTA spring boot console log Positive matches Negative matches Exclusions Unconditional classes

CONDITION EVALUATION DELTA is a feature by spring boot developer tool which evaluates bean changes. The spring boot developer tool evaluate the spring boot application on inititalization. CONDITION EVALUATION DELTA comprises four types of information namely Positive matches, Negative matches, Exclusions and Unconditional classes On every restart, spring boot application shows

@ConditionalOnMissingBean did not find any beans (OnBeanCondition)

The spring boot application runs on auto configuration mode. On a configuration change, that matches a dependent class but not loaded in the bean factory. Auto Configuration Report Root Cause If the spring boot application configuration has changed and if @ConditionalOnMissingBean matches the condition and the bean is not loaded

ConditionalOnClass found required class

If auto configuration is enabled in spring boot application and the ConditionalOnClass property is modified, the dependent class shows in auto configuration report Auto Configuration Report Negative matches: JpaBaseConfiguration.JpaWebConfiguration: Did not match: - @ConditionalOnProperty (spring.jpa.open-in-view=true) found different value in property 'open-in-view' (OnPropertyCondition) Matched: - @ConditionalOnClass found required class 'org.springframework.web.servlet.config.annotation.WebMvcConfigurer' (OnClassCondition)

ConditionalOnProperty found different open-in-view

If spring boot application is running and any of the property configuration is modified in configuration files like application.properties, This auto configuration report will be shown in console log. Auto Configuration Report Negative matches: JpaBaseConfiguration.JpaWebConfiguration: Did not match: - @ConditionalOnProperty (spring.jpa.open-in-view=true) found different value in property 'open-in-view' (OnPropertyCondition) Positive matches: