Java Bean 属性不可读或具有无效的 getter 方法:getter 的返回类型是否与 setter 的参数类型匹配?春批
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Bean property is not readable or has an invalid getter method: Does the return type of the getter match the parameter type of the setter? Spring Batch
提问by
I am developing Spring Batch CompositeItemReader & Writer
Example. I developed XML file and able to compile code successfully, but when running mu sample code gives me following error. Not sure what is going wrong?
我正在开发Spring Batch CompositeItemReader & Writer
示例。我开发了 XML 文件并且能够成功编译代码,但是在运行 mu 示例代码时出现以下错误。不知道出了什么问题?
org.springframework.beans.NotReadablePropertyException: Invalid property 'customerNumber' of bean class [java.lang.String]: Bean property 'customerNumber' is not readable or has an invalid getter method: Does the return type of the getter match the parameter type of the setter?
at org.springframework.beans.AbstractNestablePropertyAccessor.getPropertyValue(AbstractNestablePropertyAccessor.java:619)
at org.springframework.beans.AbstractNestablePropertyAccessor.getPropertyValue(AbstractNestablePropertyAccessor.java:610)
at org.springframework.batch.item.file.transform.BeanWrapperFieldExtractor.extract(BeanWrapperFieldExtractor.java:57)
at org.springframework.batch.item.file.transform.ExtractorLineAggregator.aggregate(ExtractorLineAggregator.java:54)
at org.springframework.batch.item.file.FlatFileItemWriter.write(FlatFileItemWriter.java:267)
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:497)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:190)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
at org.springframework.aop.support.DelegatingIntroductionInterceptor.doProceed(DelegatingIntroductionInterceptor.java:133)
at org.springframework.aop.support.DelegatingIntroductionInterceptor.invoke(DelegatingIntroductionInterceptor.java:121)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207)
at com.sun.proxy.$Proxy4.write(Unknown Source)
at org.springframework.batch.core.step.item.SimpleChunkProcessor.writeItems(SimpleChunkProcessor.java:175)
at org.springframework.batch.core.step.item.SimpleChunkProcessor.doWrite(SimpleChunkProcessor.java:151)
at org.springframework.batch.core.step.item.SimpleChunkProcessor.write(SimpleChunkProcessor.java:274)
at org.springframework.batch.core.step.item.SimpleChunkProcessor.process(SimpleChunkProcessor.java:199)
at org.springframework.batch.core.step.item.ChunkOrientedTasklet.execute(ChunkOrientedTasklet.java:75)
at org.springframework.batch.core.step.tasklet.TaskletStep$ChunkTransactionCallback.doInTransaction(TaskletStep.java:406)
at org.springframework.batch.core.step.tasklet.TaskletStep$ChunkTransactionCallback.doInTransaction(TaskletStep.java:330)
at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:133)
at org.springframework.batch.core.step.tasklet.TaskletStep.doInChunkContext(TaskletStep.java:271)
at org.springframework.batch.core.scope.context.StepContextRepeatCallback.doInIteration(StepContextRepeatCallback.java:77)
at org.springframework.batch.repeat.support.RepeatTemplate.getNextResult(RepeatTemplate.java:368)
at org.springframework.batch.repeat.support.RepeatTemplate.executeInternal(RepeatTemplate.java:215)
at org.springframework.batch.repeat.support.RepeatTemplate.iterate(RepeatTemplate.java:144)
at org.springframework.batch.core.step.tasklet.TaskletStep.doExecute(TaskletStep.java:257)
at org.springframework.batch.core.step.AbstractStep.execute(AbstractStep.java:198)
at org.springframework.batch.core.job.SimpleStepHandler.handleStep(SimpleStepHandler.java:148)
at org.springframework.batch.core.job.flow.JobFlowExecutor.executeStep(JobFlowExecutor.java:64)
at org.springframework.batch.core.job.flow.support.state.StepState.handle(StepState.java:67)
at org.springframework.batch.core.job.flow.support.SimpleFlow.resume(SimpleFlow.java:162)
at org.springframework.batch.core.job.flow.support.SimpleFlow.start(SimpleFlow.java:141)
at org.springframework.batch.core.job.flow.FlowJob.doExecute(FlowJob.java:134)
at org.springframework.batch.core.job.AbstractJob.execute(AbstractJob.java:304)
at org.springframework.batch.core.launch.support.SimpleJobLauncher.run(SimpleJobLauncher.java:135)
at org.springframework.core.task.SyncTaskExecutor.execute(SyncTaskExecutor.java:50)
at org.springframework.batch.core.launch.support.SimpleJobLauncher.run(SimpleJobLauncher.java:128)
at com.common.batch.main.CompositeMain.main(CompositeMain.java:24)
jdbc-composite-item-reader-job.xml
jdbc-composite-item-reader-job.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:batch="http://www.springframework.org/schema/batch" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="
http://www.springframework.org/schema/batch http://www.springframework.org/schema/batch/spring-batch.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
<import resource="classpath:context-datasource.xml" />
<!-- JobRepository and JobLauncher are configuration/setup classes -->
<bean id="jobRepository" class="org.springframework.batch.core.repository.support.MapJobRepositoryFactoryBean" />
<bean id="jobLauncher" class="org.springframework.batch.core.launch.support.SimpleJobLauncher">
<property name="jobRepository" ref="jobRepository" />
</bean>
<!-- Step will need a transaction manager -->
<bean id="transactionManager"
class="org.springframework.batch.support.transaction.ResourcelessTransactionManager" />
<!-- =========================================================== -->
<job id="compositeJdbcReaderJob" xmlns="http://www.springframework.org/schema/batch">
<step id="compositeJdbcReaderStep" next="compositeJdbcReaderStep2">
<tasklet>
<chunk reader="compositeItemReader" writer="itemWriter" commit-interval="5" />
</tasklet>
</step>
<step id="compositeJdbcReaderStep2">
<tasklet>
<chunk reader="compositeItemReader2" writer="itemWriter2" commit-interval="5" />
</tasklet>
</step>
</job>
<!-- ============= Composite Item Reader ================ -->
<bean id="compositeItemReader" class="com.common.batch.reader.CompositeCursorItemReader">
<property name="unifyingMapper">
<bean class="com.common.batch.mapper.DefaultUnifyingStringItemsMapper" />
</property>
<property name="cursorItemReaders">
<list>
<ref bean="itemReader1" />
</list>
</property>
</bean>
<bean id="compositeItemReader2" class="com.common.batch.reader.CompositeCursorItemReader">
<property name="unifyingMapper">
<bean class="com.common.batch.mapper.DefaultUnifyingStringItemsMapper" />
</property>
<property name="cursorItemReaders">
<list>
<ref bean="itemReader2" />
</list>
</property>
</bean>
<!-- ========== ItemReader =============== -->
<bean id="itemReader1" class="org.springframework.batch.item.database.JdbcCursorItemReader">
<property name="dataSource" ref="dataSource" />
<property name="saveState" value="true" />
<property name="sql">
<value>
<![CDATA[ ${select.sql.customers} ]]>
</value>
</property>
<property name="rowMapper">
<bean class="com.common.batch.mapper.CustomerMapper" />
</property>
</bean>
<bean id="itemReader2" class="org.springframework.batch.item.database.JdbcCursorItemReader">
<property name="dataSource" ref="dataSource" />
<property name="saveState" value="true" />
<property name="sql">
<value>
<![CDATA[ ${select.sql.employees} ]]>
</value>
</property>
<property name="rowMapper">
<bean class="com.common.batch.mapper.EmployeeMapper" />
</property>
</bean>
<!-- ============= Flat File Writters ============= -->
<bean id="itemWriter" class="org.springframework.batch.item.file.FlatFileItemWriter" scope="step">
<property name="resource" value="${output.file.location}" />
<!-- <property name="appendAllowed" value="true" /> -->
<property name="lineAggregator">
<!-- An Aggregator which converts an object into delimited list of strings -->
<bean class="org.springframework.batch.item.file.transform.DelimitedLineAggregator">
<property name="delimiter" value="|" />
<property name="fieldExtractor">
<!-- Extractor which returns the value of beans property through reflection -->
<bean class="org.springframework.batch.item.file.transform.BeanWrapperFieldExtractor">
<property name="names" value="customerNumber,customerName,contactLastName,contactFirstName,phone,addressLine1,
addressLine2,city,state,postalCode,country,salesRepEmployeeNumber,creditLimit" />
</bean>
</property>
</bean>
</property>
</bean>
<bean id="itemWriter2" class="org.springframework.batch.item.file.FlatFileItemWriter" scope="step">
<property name="resource" value="${output.file.location}" />
<property name="appendAllowed" value="true" />
<property name="lineAggregator">
<!-- An Aggregator which converts an object into delimited list of strings -->
<bean class="org.springframework.batch.item.file.transform.DelimitedLineAggregator">
<property name="delimiter" value="|" />
<property name="fieldExtractor">
<!-- Extractor which returns the value of beans property through reflection -->
<bean class="org.springframework.batch.item.file.transform.BeanWrapperFieldExtractor">
<property name="names" value="employeeNumber,lastName,firstName,extension,email,officeCode,reportsTo,jobTitle" />
</bean>
</property>
</bean>
</property>
</bean>
</beans>
Employee.java
雇员.java
public class Employee implements Serializable{
private static final long serialVersionUID = 1L;
private Integer employeeNumber;
private String lastName;
private String firstName;
private String extension;
private String email;
private String officeCode;
private Integer reportsTo;
private String jobTitle;
// setters and getters
}
Customer.java
客户.java
public class Customer implements Serializable{
private static final long serialVersionUID = 1L;
private Integer customerNumber;
private String customerName;
private String contactLastName;
private String contactFirstName;
private String phone;
private String addressLine1;
private String addressLine2;
private String city;
private String state;
private String postalCode;
private String country;
private Integer salesRepEmployeeNumber;
private Double creditLimit;
public Integer getCustomerNumber() {
return customerNumber;
}
public void setCustomerNumber(Integer customerNumber) {
this.customerNumber = customerNumber;
}
public String getCustomerName() {
return customerName;
}
public void setCustomerName(String customerName) {
this.customerName = customerName;
}
public String getContactLastName() {
return contactLastName;
}
public void setContactLastName(String contactLastName) {
this.contactLastName = contactLastName;
}
public String getContactFirstName() {
return contactFirstName;
}
public void setContactFirstName(String contactFirstName) {
this.contactFirstName = contactFirstName;
}
public String getPhone() {
return phone;
}
public void setPhone(String phone) {
this.phone = phone;
}
public String getAddressLine1() {
return addressLine1;
}
public void setAddressLine1(String addressLine1) {
this.addressLine1 = addressLine1;
}
public String getAddressLine2() {
return addressLine2;
}
public void setAddressLine2(String addressLine2) {
this.addressLine2 = addressLine2;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
public String getState() {
return state;
}
public void setState(String state) {
this.state = state;
}
public String getPostalCode() {
return postalCode;
}
public void setPostalCode(String postalCode) {
this.postalCode = postalCode;
}
public String getCountry() {
return country;
}
public void setCountry(String country) {
this.country = country;
}
public Integer getSalesRepEmployeeNumber() {
return salesRepEmployeeNumber;
}
public void setSalesRepEmployeeNumber(Integer salesRepEmployeeNumber) {
this.salesRepEmployeeNumber = salesRepEmployeeNumber;
}
public Double getCreditLimit() {
return creditLimit;
}
public void setCreditLimit(Double creditLimit) {
this.creditLimit = creditLimit;
}
/*@Override
public String toString() {
return customerNumber + "|" + customerName + "|" + contactLastName + "|" + contactFirstName + "|" +
phone+ "|" + addressLine1 + "|" + addressLine2 + "|" + city + "|" + state+ "|" + postalCode + "|" +
country+ "|" + salesRepEmployeeNumber + "|" + creditLimit;
}*/
}
CompositeMain.java
复合主程序
public class CompositeMain {
@SuppressWarnings("resource")
public static void main(String[] args) {
ApplicationContext context = new ClassPathXmlApplicationContext("composite/jdbc-composite-item-reader-job.xml");
JobLauncher jobLauncher = (JobLauncher) context.getBean("jobLauncher");
Job job = (Job) context.getBean("compositeJdbcReaderJob");
JobExecution execution;
try {
execution = jobLauncher.run(job, new JobParameters());
System.out.println("Job Exit Status : "+ execution.getStatus());
} catch (JobExecutionAlreadyRunningException | JobRestartException
| JobInstanceAlreadyCompleteException | JobParametersInvalidException e) {
System.out.println(e.getMessage());
e.printStackTrace();
}
System.out.println("Done !!");
}
}
My DB details:
我的数据库详细信息:
mysql> desc customers;
+------------------------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------------+-------------+------+-----+---------+-------+
| customerNumber | int(11) | NO | PRI | NULL | |
| customerName | varchar(50) | NO | | NULL | |
| contactLastName | varchar(50) | NO | | NULL | |
| contactFirstName | varchar(50) | NO | | NULL | |
| phone | varchar(50) | NO | | NULL | |
| addressLine1 | varchar(50) | NO | | NULL | |
| addressLine2 | varchar(50) | YES | | NULL | |
| city | varchar(50) | NO | | NULL | |
| state | varchar(50) | YES | | NULL | |
| postalCode | varchar(15) | YES | | NULL | |
| country | varchar(50) | NO | | NULL | |
| salesRepEmployeeNumber | int(11) | YES | MUL | NULL | |
| creditLimit | double | YES | | NULL | |
+------------------------+-------------+------+-----+---------+-------+
13 rows in set (0.14 sec)
mysql> desc employees;
+----------------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------+--------------+------+-----+---------+-------+
| employeeNumber | int(11) | NO | PRI | NULL | |
| lastName | varchar(50) | NO | | NULL | |
| firstName | varchar(50) | NO | | NULL | |
| extension | varchar(10) | NO | | NULL | |
| email | varchar(100) | NO | | NULL | |
| officeCode | varchar(10) | NO | MUL | NULL | |
| reportsTo | int(11) | YES | MUL | NULL | |
| jobTitle | varchar(50) | NO | | NULL | |
+----------------+--------------+------+-----+---------+-------+
8 rows in set (0.01 sec)
I see issue is already there: http://forum.spring.io/forum/spring-projects/container/112929-concurrent-problem-with-beanwrapperimpl-getpropertyvalue-in-3-1
我看到问题已经存在:http: //forum.spring.io/forum/spring-projects/container/112929-concurrent-problem-with-beanwrapperimpl-getpropertyvalue-in-3-1
pom.xml
pom.xml
<properties>
<java.version>1.8</java.version>
<springframework.version>4.2.4.RELEASE</springframework.version>
<springbatch.version>3.0.1.RELEASE</springbatch.version>
<mysql.version>5.1.31</mysql.version>
<joda-time.version>2.8</joda-time.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>${springframework.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>${springframework.version}</version>
</dependency>
<!-- Spring XML to/back object -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-oxm</artifactId>
<version>${springframework.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>${springframework.version}</version>
</dependency>
<!-- Spring Batch -->
<dependency>
<groupId>org.springframework.batch</groupId>
<artifactId>spring-batch-core</artifactId>
<version>${springbatch.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.batch</groupId>
<artifactId>spring-batch-infrastructure</artifactId>
<version>${springbatch.version}</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>${mysql.version}</version>
</dependency>
<dependency>
<groupId>joda-time</groupId>
<artifactId>joda-time</artifactId>
<version>${joda-time.version}</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
</dependency>
</dependencies>
CustomerMapper.java
客户映射器
public class CustomerMapper implements RowMapper<Customer>{
@Override
public Customer mapRow(ResultSet rs, int rowNum) throws SQLException {
Customer customer = new Customer();
customer.setCustomerNumber(rs.getInt("customerNumber"));
customer.setCustomerName(rs.getString("customerName"));
customer.setContactLastName(rs.getString("contactLastName"));
customer.setContactFirstName(rs.getString("contactFirstName"));
customer.setPhone(rs.getString("phone"));
customer.setAddressLine1(rs.getString("addressLine1"));
customer.setAddressLine2(rs.getString("addressLine2"));
customer.setCity(rs.getString("city"));
customer.setState(rs.getString("state"));
customer.setPostalCode(rs.getString("postalCode"));
customer.setCountry(rs.getString("country"));
customer.setSalesRepEmployeeNumber(rs.getInt("salesRepEmployeeNumber"));
customer.setCreditLimit(rs.getDouble("creditLimit"));
return customer;
}
}
EmployeeMapper.java
EmployeeMapper.java
public class EmployeeMapper implements RowMapper<Employee>{
@Override
public Employee mapRow(ResultSet rs, int rowNum) throws SQLException {
Employee employee = new Employee();
employee.setEmployeeNumber(rs.getInt("employeeNumber"));
employee.setLastName(rs.getString("lastName"));
employee.setFirstName(rs.getString("firstName"));
employee.setExtension(rs.getString("extension"));
employee.setEmail(rs.getString("email"));
employee.setOfficeCode(rs.getString("officeCode"));
employee.setReportsTo(rs.getInt("reportsTo"));
employee.setJobTitle(rs.getString("jobTitle"));
return employee;
}
}
CompositeCursorItemReader.java
CompositeCursorItemReader.java
public class CompositeCursorItemReader<T> implements ItemStreamReader<T> {
private List<AbstractCursorItemReader<?>> cursorItemReaders;
private UnifyingItemsMapper<T> unifyingMapper;
@Override
public T read() throws Exception, UnexpectedInputException, ParseException, NonTransientResourceException {
// read from all registered readers
List items = new ArrayList();
for (AbstractCursorItemReader<?> cursorItemReader : cursorItemReaders) {
items.add(cursorItemReader.read());
}
// delegate to mapper
return unifyingMapper.mapItems(items);
}
@Override
public void update(ExecutionContext executionContext) {
for (ItemStream itemStream : cursorItemReaders) {
itemStream.update(executionContext);
}
}
@Override
public void close() throws ItemStreamException {
for (ItemStream itemStream : cursorItemReaders) {
itemStream.close();
}
}
@Override
public void open(ExecutionContext executionContext) throws ItemStreamException {
for (ItemStream itemStream : cursorItemReaders) {
itemStream.open(executionContext);
}
}
public void setUnifyingMapper(UnifyingItemsMapper<T> mapper) {
this.unifyingMapper = mapper;
}
public void setCursorItemReaders(List<AbstractCursorItemReader<?>> cursorItemReaders) {
this.cursorItemReaders = cursorItemReaders;
}
}
UnifyingItemsMapper.java
UnifyingItemsMapper.java
public interface UnifyingItemsMapper<T> {
T mapItems(List<?> items) throws Exception;
}
采纳答案by Rafik BELDI
Spring is trying to get the property cutomerNumber
from the String
class :
Spring 试图cutomerNumber
从String
类中获取属性:
Invalid property 'customerNumber' of bean class [java.lang.String]
which is wrong because the String
is not supposed to be configured as the item
of your job 's step, the Item
in this context is supposed to be the Customer
.
这是错误的,因为String
不应该被配置为item
您工作的步骤,Item
在这种情况下应该是Customer
.
your beans are configured correctly except for one bean :compositeItemReader
除了一个 bean 外,您的 bean 配置正确:compositeItemReader
The read method of this bean is returning a String
instead of a Customer
which is because of this :
这个 bean 的 read 方法返回 aString
而不是 aCustomer
这是因为:
public class CompositeCursorItemReader<T> implements ItemStreamReader<T> {
/** Registered ItemStreamReaders. */
private List<AbstractCursorItemReader<?>> cursorItemReaders;
/** Mandatory Unifying Mapper Implementation. */
private UnifyingItemsMapper<T> unifyingMapper;
@Override
public T read() throws Exception, UnexpectedInputException, ParseException, NonTransientResourceException {
// read from all registered readers
List items = new ArrayList();
for (AbstractCursorItemReader<?> cursorItemReader : cursorItemReaders) {
items.add(cursorItemReader.read());
}
// delegate to mapper
return unifyingMapper.mapItems(items);
}
}
Its property UnifyingMapper is configured as follow:
其属性 UnifyingMapper 配置如下:
<property name="unifyingMapper">
<bean class="com.common.batch.mapper.DefaultUnifyingStringItemsMapper" />
</property>
here is the implementation of the UnifyingItemsMapper
you are using:
这是UnifyingItemsMapper
您正在使用的实现:
public class DefaultUnifyingStringItemsMapper implements UnifyingItemsMapper<String> {
/** {@inheritDoc} */
@Override
public String mapItems(List<?> items) throws Exception {
if (items != null && items.size() > 0) {
StringBuilder sb = new StringBuilder();
for (Object item : items) {
if (item != null) {
sb.append(item);
}
}
if (sb.length() > 0) {
return sb.toString();
} else {
return null;
}
} else {
return null;
}
}
}
the solution to this is to create a new Class that implements UnifyingItemsMapper<Customer>
and configure it for your CompositeCursorItemReader#unifyingMapper
解决这个问题的方法是创建一个新的类,UnifyingItemsMapper<Customer>
为您实现和配置它CompositeCursorItemReader#unifyingMapper
Or just use your itemReader
directly if you don't need a UnifyingItemsMapper
:
或者,itemReader
如果您不需要,则直接使用您的UnifyingItemsMapper
:
<job id="compositeJdbcReaderJob" xmlns="http://www.springframework.org/schema/batch">
<step id="compositeJdbcReaderStep" next="compositeJdbcReaderStep2">
<tasklet>
<chunk reader="itemReader1" writer="itemWriter" commit-interval="5" />
</tasklet>
</step>
<step id="compositeJdbcReaderStep2">
<tasklet>
<chunk reader="itemReader2" writer="itemWriter2" commit-interval="5" />
</tasklet>
</step>
</job>
回答by pczeus
You declare your class Customer as:
您将类 Customer 声明为:
public class Customer implements Serializable{
private static final long serialVersionUID = 1L;
private Integer customerNumber;
private String customerName;
private String contactLastName;
private String contactFirstName;
....
// setters and getters
}
All of your fields are private and you have not yet implemented public getter/setter methods. Do that and your issue will be solved.
您的所有字段都是私有的,并且您尚未实现公共 getter/setter 方法。这样做,您的问题将得到解决。