java 7 try with resource compatibility

• Contact: Jody Garnett

• Tracker: https://osgeo-org.atlassian.net/browse/GEOT-4191

• Tagline: try-with-resource

Description

Reading the Java 7 planned try-with-resource syntax I am convinced that supporting the Closable interface is necessary change for GeoTools 9.x.

Reading:

• The try-with-resources Statement (Java Tutorials)
• Eclipse Juno try-with-resources statement

Status

This proposal is shaping up, ask question on the email list or vote below:

• Andrea Aime +1
• Ben Caradoc-Davies
• Christian Mueller +1
• Ian Turton +1
• Justin Deoliveira +1
• Jody Garnett +1
• Simone Giannecchini

Tasks

1. ✅ Coordinate API Change (above patches should be tested / applied together)

2. Implement Closable\

   • ✅ FeatureIterator
   • ✅ FeatureReader
   • ✅ FeatureWriter

3. ✅ A lot of this work got rolled into the FeatureCollection clean up

4. Warn / Patch downstream applications (Combined with FeatureCollection cleanup)\

   1. ✅ Patch for GeoServer
   2. ⚠️ Patch for uDig (patch ready held up waiting for 1.3.3 release)

5. Check the code examples in user guide\

   • ✅ Feature Collection try-with-resource code example
   • ✅ Geometry CRS Tutorial
   • ✅ Query Tutorial

API Changes

FeatureIterator

BEFORE:

public interface FeatureIterator<F extends Feature> {
    public boolean hasNext();
    public F next() throws java.util.NoSuchElementException;
    public void close();
}

AFTER:

import java.lang.Closable;
public interface FeatureIterator<F extends Feature> extends Closable {
    public boolean hasNext();
    public F next() throws java.util.NoSuchElementException;
    public void close() throws IOException;
}

FeatureReader

BEFORE:

public interface FeatureReader<T extends FeatureType, F extends Feature> {
    T getFeatureType();
    F next() throws IOException, IllegalArgumentException, NoSuchElementException;
    boolean hasNext() throws IOException;
    void close() throws IOException;
}

AFTER:

import java.lang.Closable;
public interface FeatureReader<T extends FeatureType, F extends Feature> extends Closable {
    T getFeatureType();
    F next() throws IOException, IllegalArgumentException, NoSuchElementException;
    boolean hasNext() throws IOException;
    void close() throws IOException;
}

FeatureWriter

BEFORE:

public interface FeatureWriter<T extends FeatureType, F extends Feature> {
    T getFeatureType();
    F next() throws IOException;
    void remove() throws IOException;
    void write() throws IOException;
    boolean hasNext() throws IOException;
    void close() throws IOException;
}

AFTER:

import java.lang.Closable;
public interface FeatureWriter<T extends FeatureType, F extends Feature> extends Closable {
    T getFeatureType();
    F next() throws IOException;
    void remove() throws IOException;
    void write() throws IOException;
    boolean hasNext() throws IOException;
    void close() throws IOException;
}