Call a method that throws exception

Question

I am writing an app to pull and display content from an atom feed. The method for that works, but I get the error "Unhandled exception: java.lang.Exception" when I try to call the method "showFeed()" in onNavigationItemSelected.

package com.myapp;
import java.net.URL;
import java.util.Iterator;
import com.sun.syndication.feed.synd.SyndEntry;
import com.sun.syndication.feed.synd.SyndFeed;
import com.sun.syndication.io.SyndFeedInput;
import com.sun.syndication.io.XmlReader;

// ... 

public boolean onNavigationItemSelected(@NonNull MenuItem item) {
    switch (item.getItemId()) {
        case R.id.navigation_home:
            showFeed();
    }
}

// ...

public void showFeed() throws Exception {

    URL url = new URL("http://feeds.feedburner.com/javatipsfeed");
    XmlReader xmlReader = null;

    try {

        xmlReader = new XmlReader(url);
        SyndFeed feeder = new SyndFeedInput().build(xmlReader);
        System.out.println("Title Value " + feeder.getAuthor());

        for (Iterator iterator = feeder.getEntries().iterator(); iterator.hasNext();) {
            SyndEntry syndEntry = (SyndEntry) iterator.next();
            System.out.println(syndEntry.getTitle());
        }
    } finally {
        if (xmlReader != null)
            xmlReader.close();
    }

}

I want to call this method in onNavigationItemSelected.

What is the exception? I guess it would be I/O exception try it write in seperate thread or use async task — Sanjeev, Mar 25 '19 at 10:23
Use a `try-catch` or add `throws Exception` to the method. Checked exceptions [*must* be handled](https://docs.oracle.com/javase/tutorial/essential/exceptions/catchOrDeclare.html). — TiiJ7, Mar 25 '19 at 10:27

score 1 · Accepted Answer · answered Mar 25 '19 at 12:54

1

Your showFeed method is throwing Exception,

public void showFeed() throws Exception

This has to be caught using try-catch block or thrown further from the caller method which is onNavigationItemSelected

So either catch it like this,

 case R.id.navigation_home:
try{
            showFeed();
} catch (Exception e) {
e.printStackTrace();
}

Or throw it again like below,

public boolean onNavigationItemSelected(@NonNull MenuItem item) throws Exception

answered Mar 25 '19 at 12:54

Santosh

874
11
21

This took away the error. Thanks. I marked this as answer because it showed an example – user2341596 Mar 27 '19 at 19:22

score 0 · Answer 2 · answered Mar 25 '19 at 10:28

0

You are running network related threads on UI Thread which may cause ANR (Activity not responding) Follow the following tutorial.

Android AsyncTask example and explanation

answered Mar 25 '19 at 10:28

Sanjeev

292
2
5
24

Call a method that throws exception

2 Answers2