Develop Reference

How to handle only ClientAbortException?

I am coding a download file controller
Sometime user will close the browser window before the file is fully written. - which is cool.
The problem is that my logs are full of this error:
org.apache.catalina.connector.ClientAbortException: java.io.IOException: An established connection was aborted by the software in your host machine
at org.apache.catalina.connector.OutputBuffer.realWriteBytes(OutputBuffer.java:333)
at org.apache.catalina.connector.OutputBuffer.flushByteBuffer(OutputBuffer.java:758)
at org.apache.catalina.connector.OutputBuffer.append(OutputBuffer.java:663)
at org.apache.catalina.connector.OutputBuffer.writeBytes(OutputBuffer.java:368)
at org.apache.catalina.connector.OutputBuffer.write(OutputBuffer.java:346)
at org.apache.catalina.connector.CoyoteOutputStream.write(CoyoteOutputStream.java:96)
at org.apache.commons.io.IOUtils.copyLarge(IOUtils.java:2147)
at org.apache.commons.io.IOUtils.copy(IOUtils.java:2102)
at org.apache.commons.io.IOUtils.copyLarge(IOUtils.java:2123)
at org.apache.commons.io.IOUtils.copy(IOUtils.java:2078)
When I am trying to catch only this specific error eclipse is saying:
ClientAbortException cannot be resolved to a type
I have the project setup and running correctly so is it possible to catch only this specific exception:
org.apache.catalina.connector.ClientAbortException
I would like to keep the IOException in case of another catastrophe.

The ClientAbortException is derived from IOException. You have to inspect exactly what exception caused the IOException e:
...
} catch (FileNotFoundException fnfe) {
// ... handle FileNotFoundException
} catch (IOException e) {
String exceptionSimpleName = e.getCause().getClass().getSimpleName();
if ("ClientAbortException".equals(exceptionSimpleName)) {
// ... handle ClientAbortException
} else {
// ... handle general IOException or another cause
}
}
return null;

Instead of looking for a certain class name (that ties your application to a specific servlet container) I usually handle IOExceptions on write differently than IOExceptions on read, like so (very pseudo-ish code):
try {
byte[] buffer = ...
in.read(buffer);
try {
out.write(buffer);
} catch (IOException writeException) {
// client aborted request
}
} catch (IOException readException) {
// something went wrong -> signal 50x or something else
}
Worked out quite fine so far.

(As of #Nikolas Charalambidis answer)
Ignore "org.apache.catalina.connector.ClientAbortException:java.io.IOException: Connection reset by peer"
e.getCause().getClass().getSimpleName() == "IOException"
e.getMessage() == "java.io.IOException: Connection reset by peer"
And don't handle general IOException and another cause
...
} catch (IOException e) {
if (! e.getMessage().contains("Connection reset by peer")) {
throw e;
}
} finally {
close(output);
close(input);
}
...

Android unreported exception IOException error

I am new to android apps development. Recently,Im writing an application which able to show public ip based on Ipify. So far, i already:
Download the required jar file and put inside libs folder
I also compile file within gradle
Then i import required class it to my class
How to use Ipify, according to its website:
import org.ipify.Ipify;
public class HelloIP {
public static void main(String[] args) throws IOException {
System.out.println(Ipify.getPublicIp());
}
}
I write the following method to be invoked from another class:
public static String getPublicIp() throws IOException{
String ip = Ipify.getPublicIp();
return ip;
}
Another Class
//Get wifi
getWifiName wifiInfo = new getWifiName();
String myIP = wifiInfo.getPublicIp();
However, i keep getting:
Error:(52, 43) error: unreported exception IOException; must be caught
or declared to be thrown
I tried to modify the code and use the following try and catch, but still got the same error.
public static String getPublicIp() throws IOException{
String myip = Ipify.getPublicIp();
try{
return myip;
}
catch (IOException e){
System.out.println("General I/O exception: " + e.getMessage());
e.printStackTrace();
}
}
Im not too good in catch and throw exception, and already spent the whole day for this.I dont have idea anymore to fix this error..T.T

public static String getPublicIp() {
try{
return Ipify.getPublicIp();
}catch (IOException e){
System.out.println("General I/O exception: " + e.getMessage());
e.printStackTrace();
}
return null;
}
In case it didn't help, clean project in your IDE. You may have some data cached and it might be a reason.
Your problem is in another class! As you have declared the method getPublicIp() to throw IOException that class is afraid of receiving the Exception and therefor requests catching it.
In Java you have two types of Exceptions. Checked and unchecked. Checked Exceptions must be caught.
In Java Exceptions are used for marking unexpected situations. For example parsing non-numeric String to a number (NumberFormatException) or calling a method on a null reference (NullPointerException). You can catch them in many ways.
Unchecked Exceptions are those which extend RunTimeException. They are used for marking unexpected states usually caused by user's input. They shouldn't cause harm and should be worked out with business logic. You don't have to catch them, but sometimes you should.
On the other hand there are Checked Exceptions which mark dangerous situations. For example the application being unable to open a file. As those situations are found dangerous, you must catch them.
try{
//some code
} catch (NumberFormatException e1) {
e.printStackTrace() //very important - handles the Exception but prints the information!
} catch (NullPointerException e2) {
e.printStackTrace();
}
or using the fact, that they all extend Exception:
try {
//somecode
} catch (Exception e) {
e.printStackTrace;
};
or since Java 7:
try {
//somecode
} catch (NullPointerException | NumberFormatException e) {
e.printStackTrace;
};

How to catch JVM_Bind exception: java.net.BindException: Address already in use

How can i catch the Bind exception? i used the following lines
try{
//some code
}
catch (java.net.BindException e) {
//some code
}
and
try{
//some code
}catch (BindException e) {
//some code
}
but none of them is working giving me the error
`java.net.BindException: Address already in use: JVM_Bind
java.net.DualStackPlainSocketImpl.bind0(Native Method)
java.net.DualStackPlainSocketImpl.socketBind(DualStackPlainSocketImpl.java:106)
java.net.AbstractPlainSocketImpl.bind(AbstractPlainSocketImpl.java:376)
java.net.PlainSocketImpl.bind(PlainSocketImpl.java:190)
java.net.ServerSocket.bind(ServerSocket.java:376)
java.net.ServerSocket.<init>(ServerSocket.java:237)
...
Can anybody give me an idea? Thanks in advance :)

Are you sure that the try block surrounds the code that throws the exception? I say, either it's not, or that the BindException is wrapped with some other Throwable before thrown. In that case, try
try {
// the problematic code
} catch (Throwable t) { // <--- here, Throwable
// better log the error here
}

Apache POI Runtimeexception on close()

I have a problem using Apache POI to read some .docx contents and show the result as unformatted preview. Im using POI version 3.11.
Code:
private static String POI2Text(File file) {
POITextExtractor extractor = null;
try {
extractor = ExtractorFactory.createExtractor(file);
return extractor.getText();
} catch (Exception ex) {
logger.warn("Error:", ex);
} finally {
if (extractor!=null) try { extractor.close(); } catch (Exception ex) { logger.warn("Error:", ex); }
}
return "";
}
The following Exception is thrown in the finally block (extractor.close()):
org.apache.poi.openxml4j.exceptions.OpenXML4JRuntimeException: Fail to save: an error occurs while > saving the package : part
at org.apache.poi.openxml4j.opc.ZipPackage.saveImpl(ZipPackage.java:503) ~[agent.jar:na]
at org.apache.poi.openxml4j.opc.OPCPackage.save(OPCPackage.java:1425) ~[agent.jar:na]
at org.apache.poi.openxml4j.opc.OPCPackage.save(OPCPackage.java:1412) ~[agent.jar:na]
at org.apache.poi.openxml4j.opc.ZipPackage.closeImpl(ZipPackage.java:353) ~[agent.jar:na]
at org.apache.poi.openxml4j.opc.OPCPackage.close(OPCPackage.java:425) ~[agent.jar:na]
at org.apache.poi.POIXMLTextExtractor.close(POIXMLTextExtractor.java:87) ~[agent.jar:na]
....
Caused by: java.lang.IllegalArgumentException: part
at org.apache.poi.openxml4j.opc.OPCPackage.addPackagePart(OPCPackage.java:873) ~[agent.jar:na]
at org.apache.poi.openxml4j.opc.ZipPackage.saveImpl(ZipPackage.java:448) ~[agent.jar:na]
... 15 common frames omitted
Any ideas how to prevent this exception? The biggest problem is, that poi doesn't release the file handle after the exception is thrown. I need to be able to move or edit the file outside of my app.

Just a quick feedback: I could resolve the issue by opening an inputstream as read-only and then using this stream to extract data with the POITextExtractor.
try (InputStream is = Files.newInputStream(path, StandardOpenOption.READ);
POITextExtractor extractor = ExtractorFactory.createExtractor(is)) {
return extractor.getText();
} catch (Exception ex) {
logger.warn("Error in file {}", path, ex);
}

IOException: Read Error

If you want more info on the error, the full source can be downloaded here
Hey, I'm reading an ini file using java.util.Properties; and I've run into a strange issue. When I try to load a specific file, the thing spits out this strange exception that I've been trying for about a day to eliminate.
java.io.IOException: Read error
at java.io.FileInputStream.readBytes(Native Method)
at java.io.FileInputStream.read(Unknown Source)
at java.util.Properties$LineReader.readLine(Unknown Source)
at java.util.Properties.load0(Unknown Source)
at java.util.Properties.load(Unknown Source)
at IniReader.load(IniReader.java:20)
at plane.<init>(plane.java:22)
at renderingArea.<init>(flight_optimizer.java:93)
at flight_optimizer_GUI.<init>(flight_optimizer.java:159)
at flight_optimizer.main(flight_optimizer.java:46)
I had previously been reading this file just fine with no problems, I then changed a bit of how I was calling and had to add an extra line at the bottom. If I remove that line, the problem does not occour.
the txt file is:
x=0
y=0
max_velocity=.1
passengers=100
num_planes=1
If I remove the num_planes=1 line, the file gets read fine.
Relevant code:
import java.util.Enumeration;
public class IniReader {
//global vars
public IniReader(){
// initializeing stuffs
}
public void load(InputStream inStream) throws IOException {
this.inStream = inStream;
this.properties.load(this.inStream);
this.keys = this.properties.propertyNames();
inStream.close();
}
}
class renderingArea extends JPanel {
//Global vars
private IniReader ini;
public renderingArea(){
super();
// Initializing some things
files = new fileManager();
ini = new IniReader();
FileInputStream planeStream;
FileInputStream cityStream;
try {
planeStream = files.getIni("plane.ini");
ini.load(planeStream);
//extraneous code
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e1) {
e1.printStackTrace();
} catch (NumberFormatException e1) {
e1.printStackTrace();
}
}
//moar extraneous code
}

That is why:
Your code (flight_optimizer.java, line 82 and further):
FileInputStream planeStream;
...
planeStream = files.getIni("plane.ini");
ini.load(planeStream);
...
for( int i=0; i<planes.length; i++ ){
planes[i] = new plane(planeStream);
}
Both the second line and every cycle iteration leads us here (IniReader.java, line 17):
public void load(InputStream inStream) throws IOException {
this.inStream = inStream;
this.properties.load(this.inStream);
this.keys = this.properties.propertyNames();
inStream.close();
}
You are trying to use the same InputStream multiple times, moreover, you are trying to use it after it already was closed. You will need to recreate the stream, or, preferably, read configuration once and use it multiple times.
As a side note, the recommended way to use the streams in Java is the following:
InputStream is = ...;
try {
// Reading from the stream
} finally {
is.close();
}
This will make sure that the system resources associated with the stream will always be released.

I had the same problem. Turns out that my underlying InputStream was already closed. That became obvious when I ran my test under Linux, where a more meaningful error message was emitted by the operating system.