Java Properties Load from File loadProperties(ProcessingEnvironment env, String fileName)

Description

Attempts to load fileName and return its properties.

License

Apache License

Declaration

public static Map<String, String> loadProperties(ProcessingEnvironment env, String fileName)

Method Source Code


//package com.java2s;
//License from project: Apache License 

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Properties;
import javax.annotation.processing.ProcessingEnvironment;
import javax.tools.FileObject;
import javax.tools.StandardLocation;
import javax.tools.JavaFileManager.Location;

public class Main {
    /** Attempts to load {@code fileName} and return its properties. */
    public static Map<String, String> loadProperties(ProcessingEnvironment env, String fileName) {
        Map<String, String> properties = new LinkedHashMap<String, String>();

        // Eclipse, ant, and maven all act a little differently here, so try both source and class output
        File file = null;//  w  w w.jav a2s.c om
        for (Location location : new Location[] { StandardLocation.SOURCE_OUTPUT, StandardLocation.CLASS_OUTPUT }) {
            file = resolveBindgenPropertiesIfExists(location, env, fileName);
            if (file != null) {
                break;
            }
        }

        if (file != null) {
            Properties p = new Properties();
            try {
                p.load(new FileInputStream(file));
            } catch (Exception e) {
                e.printStackTrace();
            }
            for (Map.Entry<Object, Object> entry : p.entrySet()) {
                properties.put((String) entry.getKey(), (String) entry.getValue());
            }
        }

        return properties;
    }

    /** Finds a file by starting by <code>location</code> and walkig up.
     *
     * This uses a heuristic because in Eclipse we will not know what our
     * working directory is (it is wherever Eclipse was started from), so
     * project/workspace-relative paths will not work.
     *
     * As far as passing in a the properties location as a {@code -Afile=path}
     * setting, Eclipse also lacks any {@code ${basepath}}-type interpolation
     * in its APT key/value pairs (like Ant would be able to do). So only fixed
     * values are accepted, meaning an absolute path, which would be too tied
     * to any one developer's particular machine.
     *
     * The one thing the APT API gives us is the CLASS_OUTPUT (e.g. bin/apt).
     * So we start there and walk up parent directories looking for
     * {@code bindgen.properties} files.
     */
    private static File resolveBindgenPropertiesIfExists(Location location, ProcessingEnvironment env,
            String fileName) {
        // Find a dummy /bin/apt/dummy.txt path to start at
        final String dummyPath;
        try {
            // We don't actually create this, we just want its URI
            FileObject dummyFileObject = env.getFiler().getResource(location, "", "dummy.txt");
            dummyPath = dummyFileObject.toUri().toString().replaceAll("file:", "");
        } catch (IOException e1) {
            return null;
        }

        // Walk up looking for a bindgen.properties
        File current = new File(dummyPath).getParentFile();
        while (current != null) {
            File possible = new File(current, fileName);
            if (possible.exists()) {
                return possible;
            }
            current = current.getParentFile();
        }

        // Before giving up, try just grabbing it from the current directory
        File possible = new File(fileName);
        if (possible.exists()) {
            return possible;
        }

        // No file found
        return null;
    }
}

Java Properties Load from File loadProperties(ProcessingEnvironment env, String fileName)

Description

License

Declaration

Method Source Code

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