问题描述
如果这样做的话,这里是:body ->字符串->用户
.to("direct:httpClient").process(新处理器(){@覆盖公共无效进程(交换交换)抛出 JsonProcessingException {String body = exchange.getIn().getBody(String.class);User[] users = jacksonDataFormat.getObjectMapper().readValue(body, User[].class);}})
此选项效果很好,但如果您这样做:
User [] body = exchange.getIn().getBody(User[].class);
身体->用户,它不起作用.用户始终为空.
为了清楚起见:
from("timer://test?period=2000").setHeader(Exchange.HTTP_METHOD).constant(HttpMethod.GET).setHeader(Exchange.CONTENT_TYPE, 常量("application/json")).convertBodyTo(用户[].class).to("http://localhost:8085/api/user").process(exchange -> System.out.println(exchange.getIn().getBody(String.class)))
控制台输出:
<代码>[{名称":BLA";},{名称":BLA";},{名称":BLA";}]
如果是这样:
from("timer://test?period=2000").setHeader(Exchange.HTTP_METHOD).constant(HttpMethod.GET).setHeader(Exchange.CONTENT_TYPE, 常量("application/json")).convertBodyTo(用户[].class).to("http://localhost:8085/api/user").process(exchange -> System.out.println(exchange.getIn().getBody(User[].class)))
控制台输出:null
是什么原因?我该如何解决这个问题?
解决方案
如果你想让 Camel 处理 JSON 字符串到 Java 对象的过程,你可以将它添加为 marshaller - https://camel.apache.org/components/latest/dataformats/jacksonxml-dataformat.htmlp>
Here is if do so: body -> string -> user
.to("direct:httpClient") .process(new Processor() { @Override public void process(Exchange exchange) throws JsonProcessingException { String body = exchange.getIn().getBody(String.class); User[] users = jacksonDataFormat.getObjectMapper().readValue(body, User[].class); } })
This option works great, but if you do this:
User [] body = exchange.getIn().getBody(User[].class);
body -> user, it doesn't work. User always null.
For clarity:
from("timer://test?period=2000") .setHeader(Exchange.HTTP_METHOD).constant(HttpMethod.GET) .setHeader(Exchange.CONTENT_TYPE, constant("application/json")) .convertBodyTo(User[].class) .to("http://localhost:8085/api/user") .process(exchange -> System.out.println(exchange.getIn().getBody(String.class)))
Console output:
[ { "name":"BLA" }, { "name":"BLA" }, { "name":"BLA" } ]
If so:
from("timer://test?period=2000") .setHeader(Exchange.HTTP_METHOD).constant(HttpMethod.GET) .setHeader(Exchange.CONTENT_TYPE, constant("application/json")) .convertBodyTo(User[].class) .to("http://localhost:8085/api/user") .process(exchange -> System.out.println(exchange.getIn().getBody(User[].class)))
Console output: null
What is the reason? how can I fix this?
解决方案
If you want Camel to handle the JSON string to Java object process, you can add it as a marshaller - https://camel.apache.org/components/latest/dataformats/jacksonxml-dataformat.html
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