spring boot: unable to autowire bean, but the bean is defined for sure

Question

I wrote a small spring boot program that needs to connect to a database by using jdbcTemplate. The JDBC driver is present and I set everything in application.properties:

spring.datasource.url=jdbc:oracle:thin:@servername:1521:foo
spring.datasource.username=guesswho
spring.datasource.password=iwonttell
spring.datasource.driver-class-name=oracle.jdbc.driver.OracleDriver

When I let spring boot actuator display the beans by opening localhost:8080/beans I can see my class that needs the bean ...

1:Object
bean:"mybean"
scope:"singleton"
type:"de...."
resource:"file [C:/....class]"
dependencies:Array[1]
0:"jdbcTemplate"

... and I can see the bean was defined:

56:Object
bean:"jdbcTemplate"
scope:"singleton"
type:"org.springframework.jdbc.core.JdbcTemplate"
resource:"class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceAutoConfiguration$JdbcTemplateConfiguration.class]"
dependencies:Array[0]

This is my code which shows all three variants of autowiring I tried and none of them works

public class myBean implements IMyBean {
  @Autowired
  private JdbcTemplate jdbcTemplate;

  @Autowired
  public myBean(JdbcTemplate jdbcTemplate) {
    this.jdbcTemplate = jdbcTemplate;
  }

  @Autowired
  public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
    this.jdbcTemplate = jdbcTemplate;
  }

  @Override
  public foo searchDb(String for) {
    String sql = "SELECT bar FROM ...";

    jdbcTemplate.query( sql, ...

In the last line with jdbcTemplate.query a NPE occurs.

I think I'm unable to see the forrest for the trees. I checked the suggested answers stackoverflow provides (e.g. spring-boot properties not @Autowired) but I think they don't match my problem. Help is wholeheartedly appreciated ...

can you how the stacktrace, or is it just a null pointer exception given? — Ricardo Garza V., Jan 08 '15 at 19:38
A npe is thrown when I run a method on my class which uses jdbcTemplate — Marged, Jan 08 '15 at 19:59
can you show the code of "myBean" "JdbcTemplate" and the place where you use "mybean"? it would be easier with some code — Ricardo Garza V., Jan 08 '15 at 20:04
Sure. JdbcTemplate is provided by Spring JDBC so I will skip that one. — Marged, Jan 08 '15 at 20:51
I altered my first post and added more code, please have a look at the beginning of the page — Marged, Jan 08 '15 at 20:56
and the class wich calls for myBean.searchDb? Also I asume either "myBean" or "IMyBean" are annotated by "@Service" or "@Component" — Ricardo Garza V., Jan 08 '15 at 21:19
by any chance, you wouln't be doins something like "new myBean();" would you? — Ricardo Garza V., Jan 08 '15 at 21:53
You helped me cut down the trees ... In my real code (what I showed above was a cut down version) I forgot one @AutoWired annotation — Marged, Jan 09 '15 at 12:36

score 1 · Accepted Answer · answered Jan 09 '15 at 12:41

The problem was caused by a forgotten annotation: @AutoWired was missing and because of this I had two instances. One was configured correctly and included the jdbcTemplate, the other had a null jdbcTemplate. I checked the first one, but it was not used.

spring boot: unable to autowire bean, but the bean is defined for sure

1 Answers1