Spring Boot 原因:java.lang.NoSuchFieldException:修饰符

l7mqbcuq  于 7个月前  发布在  Spring
关注(0)|答案(1)|浏览(64)

我正在使用现有的旧spring引导代码,同时迁移/升级到spring引导2.7.16和jdk版本从8升级到21我得到这个错误

import java.lang.reflect.Field;
import java.lang.reflect.Modifier;
import java.util.List;
import org.apache.log4j.Logger;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.SqlParameter;
import org.springframework.jdbc.core.simple.AbstractJdbcCall;
import org.springframework.jdbc.core.simple.SimpleJdbcCall;
public class CustomJDBCCall extends SimpleJdbcCall {
private final CustomCallMetaDataContext callMetaDataContext;
private static final String CALL_META_DATA_CONTEXT = "callMetaDataContext";
private static final String MODIFIERS = "modifiers";
private static final Logger LOGGER =Logger.getLogger(CustomJDBCCall.class);

public CustomJDBCCall(JdbcTemplate jdbcTemplate) throws Exception {
    super(jdbcTemplate);
    try {
        callMetaDataContext = new CustomCallMetaDataContext();
        
        // Access private field
        Field callMetaDataContextField = 
        AbstractJdbcCall.class.getDeclaredField(CALL_META_DATA_CONTEXT);
        callMetaDataContextField.setAccessible(true);

   
        Field modifiersField = Field.class.getDeclaredField(MODIFIERS);
        modifiersField.setAccessible(true);
        modifiersField.setInt(callMetaDataContextField, 
     callMetaDataContextField.getModifiers() & ~Modifier.FINAL);

        callMetaDataContextField.set(this, this.callMetaDataContext);
      } catch (NoSuchFieldException | IllegalAccessException ex) {
        LOGGER.error("Error while using custom JDBC", ex);
        throw new RuntimeException("Exception thrown overriding 
     AbstractJdbcCall.callMetaDataContext field", ex);
     } catch (Exception ex) {
        LOGGER.error("Error while using custom JDBC", ex);
        throw ex;
     }
   }

    public List<SqlParameter> getParamerters() throws Exception {
    return this.callMetaDataContext.getCallParameters();
    }
 }

字符串
在这段代码中,

Field modifiersField = Field.class.getDeclaredField(MODIFIERS);


原因:java.lang.NoSuchFieldException:modifiers at java.base/java.lang.Class.getDeclaredField(Class.java:2782)
之前它在jdk 8中工作正常。这是现有的代码不是我写的,我认为这里访问私有final字段并设置值。我对吗?我认为在Jdk版本12及以上修改final和私有变量是不可能的或禁用的,有没有任何工作?

dxpyg8gm

dxpyg8gm1#

在项目文件夹中添加了spring类AbstractJdbcCall.java,并使用确切的包名。然后添加以下方法以返回callMetaDataContext

public CallMetaDataContext getCallMetaDataContext() {
    return this.callMetaDataContext;
}

字符串
现在CustomJDBCCall看起来像这样

public class CustomJDBCCall extends SimpleJdbcCall {
        
 public CustomJDBCCall(JdbcTemplate jdbcTemplate) throws Exception 
  {
      super(jdbcTemplate);  
   
  }

  public List<SqlParameter> getParamerters() throws Exception {
    return this.getCallMetaDataContext().getCallParameters();
  }
 }


这解决了我的问题。

相关问题