Java 错误：目标主机不得为空，或在参数中设置
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Error: Target host must not be null, or set in parameters
提问by smiley
I am trying to send a string from one application to another. I would be returning a response which is a string. Here, myhost.com/views is the 2nd application where I need to send the string value and get a response from it. But when I am trying to send it is not executing this code. Can someone please correct me where I am wrong?
我正在尝试将一个字符串从一个应用程序发送到另一个应用程序。我将返回一个字符串响应。在这里，myhost.com/views 是我需要发送字符串值并从中获得响应的第二个应用程序。但是当我尝试发送时，它没有执行此代码。有人可以纠正我的错误吗？
Below is the code I have written.
下面是我写的代码。
public static void sendData(String strval) throws IOException{
String doSend="https://myhost.com/views?strval="+strval;
HttpClient httpclient = new DefaultHttpClient();
try {
System.out.println("inside try");
URIBuilder builder = new URIBuilder();
System.out.println("builder="+builder);
builder.setHost("myhost.com").setPath("/views");
builder.addParameter("strval", strval);
System.out.println("add param,sethost,setpath complete");
URI uri = builder.build();
System.out.println("uri="+uri);
HttpGet httpget = new HttpGet(uri);
System.out.println("httpGet"+httpget);
HttpResponse response = httpclient.execute(httpget);
System.out.println(response.getStatusLine().toString());
if (response.getStatusLine().getStatusCode() == 200) {
String responseText = EntityUtils.toString(response.getEntity());
System.out.println("responseText="+responseText);
httpclient.getConnectionManager().shutdown();
} else {
System.out.println("Server returned HTTP code "
+ response.getStatusLine().getStatusCode());
}
} catch (java.net.URISyntaxException bad) {
System.out.println("URI construction error: " + bad.toString());
}
catch(Exception e){ System.out.println("e.getMessage=>"+e.getMessage()); }
}
Code runs till and when I print the exceptions I see excep.getMessage() ->
代码运行直到我打印异常时我看到 excep.getMessage() ->
java.lang.IllegalStateException: Target host must not be null, or set in parameters.
at org.apache.http.impl.client.DefaultRequestDirector.determineRoute(DefaultRequestDirector.java:789)
at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:414)
at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:906)
at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:805)
at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:784)
采纳答案by smiley
This code is not able to recognize it as a valid URIsince it was missing http. This is what I added to resolve the code:
此代码无法将其识别为有效，URI因为它丢失了http。这是我添加来解决代码的内容：
builder.setScheme("http");
