Ant example source code file (StringResource.java)

This example Ant source code file (StringResource.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Ant tags/keywords

buildexception, bytearrayoutputstream, filteroutputstream, immutableresourceexception, inputstream, io, ioexception, ioexception, resource, resource, string, string, string_magic, stringresource, stringresource

The StringResource.java source code

/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 */

package org.apache.tools.ant.types.resources;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.FilterOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;

import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.types.Resource;
import org.apache.tools.ant.types.Reference;

/**
 * Exposes a string as a Resource.
 * @since Ant 1.7
 */
public class StringResource extends Resource {

    /** Magic number */
    private static final int STRING_MAGIC
        = Resource.getMagicNumber("StringResource".getBytes());

    private String encoding = null;

    /**
     * Default constructor.
     */
    public StringResource() {
    }

    /**
     * Construct a StringResource with the supplied value.
     * @param value the value of this StringResource.
     */
    public StringResource(String value) {
        setValue(value);
    }

    /**
     * Enforce String immutability.
     * @param s the new name/value for this StringResource.
     */
    public synchronized void setName(String s) {
        if (getName() != null) {
            throw new BuildException(new ImmutableResourceException());
        }
        super.setName(s);
    }

    /**
     * The value attribute is a semantically superior alias for the name attribute.
     * @param s the String's value.
     */
    public synchronized void setValue(String s) {
        setName(s);
    }

    /**
     * Synchronize access.
     * @return the name/value of this StringResource.
     */
    public synchronized String getName() {
        return super.getName();
    }

    /**
     * Get the value of this StringResource.
     * @return the represented String.
     */
    public synchronized String getValue() {
        return getName();
    }

    /**
     * Set the encoding to be used for this StringResource.
     * @param s the encoding name.
     */
    public synchronized void setEncoding(String s) {
        encoding = s;
    }

    /**
     * Get the encoding used by this StringResource.
     * @return the encoding name.
     */
    public synchronized String getEncoding() {
        return encoding;
    }

    /**
     * Get the size of this Resource.
     * @return the size, as a long, 0 if the Resource does not exist (for
     *         compatibility with java.io.File), or UNKNOWN_SIZE if not known.
     */
    public synchronized long getSize() {
        return isReference()
            ? ((Resource) getCheckedRef()).getSize()
            : (long) getContent().length();
    }

    /**
     * Get the hash code for this Resource.
     * @return hash code as int.
     */
    public synchronized int hashCode() {
        if (isReference()) {
            return getCheckedRef().hashCode();
        }
        return super.hashCode() * STRING_MAGIC;
    }

    /**
     * Get the string.
     *
     * @return the string contents of the resource.
     * @since Ant 1.7
     */
    public String toString() {
        if (isReference()) {
            return getCheckedRef().toString();
        }
        return String.valueOf(getContent());
    }

    /**
     * Get an InputStream for the Resource.
     * @return an InputStream containing this Resource's content.
     * @throws IOException if unable to provide the content of this
     *         Resource as a stream.
     * @throws UnsupportedOperationException if InputStreams are not
     *         supported for this Resource type.
     */
    public synchronized InputStream getInputStream() throws IOException {
        if (isReference()) {
            return ((Resource) getCheckedRef()).getInputStream();
        }
        //I can't get my head around this; is encoding treatment needed here?
        return
            //new oata.util.ReaderInputStream(new InputStreamReader(
            new ByteArrayInputStream(getContent().getBytes());
            //, encoding), encoding);
    }

    /**
     * Get an OutputStream for the Resource.
     * @return an OutputStream to which content can be written.
     * @throws IOException if unable to provide the content of this
     *         Resource as a stream.
     * @throws UnsupportedOperationException if OutputStreams are not
     *         supported for this Resource type.
     */
    public synchronized OutputStream getOutputStream() throws IOException {
        if (isReference()) {
            return ((Resource) getCheckedRef()).getOutputStream();
        }
        if (getValue() != null) {
            throw new ImmutableResourceException();
        }
        final ByteArrayOutputStream baos = new ByteArrayOutputStream();
        return new FilterOutputStream(baos) {
            public void close() throws IOException {
                super.close();
                StringResource.this.setValue(encoding == null
                    ? baos.toString() : baos.toString(encoding));
            }
        };
    }

    /**
     * Overrides the super version.
     * @param r the Reference to set.
     */
    public void setRefid(Reference r) {
        if (encoding != null) {
            throw tooManyAttributes();
        }
        super.setRefid(r);
    }

    /**
     * Get the content of this StringResource.
     * @return a String; if the Project has been set properties
     *         replacement will be attempted.
     */
    protected synchronized String getContent() {
        if (isReference()) {
            return ((StringResource) getCheckedRef()).getContent();
        }
        String value = getValue();
        if (value == null) {
            return value;
        }
        return getProject() == null
            ? value : getProject().replaceProperties(value);
    }

}