com.wl4g.infra.common.resource.FileStreamResource Maven / Gradle / Ivy
/*
* Copyright 2017 ~ 2025 the original author or authors. James Wong
*
* Licensed 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 com.wl4g.infra.common.resource;
/**
* Retention of upstream license agreement statement:
* Thank you very much spring framework, We fully comply with and support the open license
* agreement of spring. The purpose of migration is to solve the problem
* that these elegant API programs can still be easily used without running
* in the spring environment.
*
* Copyright 2002-2017 the original author or authors.
*
* Licensed 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.
*/
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URI;
import java.net.URL;
import com.wl4g.infra.common.lang.Assert2;
import com.wl4g.infra.common.lang.StringUtils2;
/**
* {@link org.springframework.core.io.FileSystemResource} implementation for
* {@code java.io.File} handles. Supports resolution as a {@code File} and also
* as a {@code URL}. Implements the extended {@link WritableStreamResource}
* interface.
*
* @author Juergen Hoeller
* @since 28.12.2003
* @see java.io.File
*/
public class FileStreamResource extends AbstractStreamResource {
private final File file;
private final String path;
/**
* Create a new {@code FileSystemResource} from a {@link File} handle.
*
* Note: When building relative resources via {@link #createRelative}, the
* relative path will apply at the same directory level: e.g. new
* File("C:/dir1"), relative path "dir2" -> "C:/dir2"! If you prefer to have
* relative paths built underneath the given root directory, use the
* {@link #FileSystemResource(String) constructor with a file path} to
* append a trailing slash to the root path: "C:/dir1/", which indicates
* this directory as root for all relative paths.
*
* @param file
* a File handle
*/
public FileStreamResource(File file) {
Assert2.notNull(file, "File must not be null");
this.file = file;
this.path = StringUtils2.cleanPath(file.getPath());
}
/**
* Create a new {@code FileSystemResource} from a file path.
*
* Note: When building relative resources via {@link #createRelative}, it
* makes a difference whether the specified resource base path here ends
* with a slash or not. In the case of "C:/dir1/", relative paths will be
* built underneath that root: e.g. relative path "dir2" -> "C:/dir1/dir2".
* In the case of "C:/dir1", relative paths will apply at the same directory
* level: relative path "dir2" -> "C:/dir2".
*
* @param path
* a file path
*/
public FileStreamResource(String path) {
Assert2.notNull(path, "Path must not be null");
this.file = new File(path);
this.path = StringUtils2.cleanPath(path);
}
/**
* Return the file path for this resource.
*/
public final String getPath() {
return this.path;
}
/**
* This implementation returns whether the underlying file exists.
*
* @see java.io.File#exists()
*/
@Override
public boolean exists() {
return this.file.exists();
}
/**
* This implementation checks whether the underlying file is marked as
* readable (and corresponds to an actual file with content, not to a
* directory).
*
* @see java.io.File#canRead()
* @see java.io.File#isDirectory()
*/
@Override
public boolean isReadable() {
return (this.file.canRead() && !this.file.isDirectory());
}
/**
* This implementation opens a FileInputStream for the underlying file.
*
* @see java.io.FileInputStream
*/
@Override
public InputStream getInputStream() throws IOException {
return new FileInputStream(this.file);
}
/**
* This implementation checks whether the underlying file is marked as
* writable (and corresponds to an actual file with content, not to a
* directory).
*
* @see java.io.File#canWrite()
* @see java.io.File#isDirectory()
*/
public boolean isWritable() {
return (this.file.canWrite() && !this.file.isDirectory());
}
/**
* This implementation opens a FileOutputStream for the underlying file.
*
* @see java.io.FileOutputStream
*/
public OutputStream getOutputStream() throws IOException {
return new FileOutputStream(this.file);
}
/**
* This implementation returns a URL for the underlying file.
*
* @see java.io.File#toURI()
*/
@Override
public URL getURL() throws IOException {
return this.file.toURI().toURL();
}
/**
* This implementation returns a URI for the underlying file.
*
* @see java.io.File#toURI()
*/
@Override
public URI getURI() throws IOException {
return this.file.toURI();
}
/**
* This implementation returns the underlying File reference.
*/
@Override
public File getFile() {
return this.file;
}
/**
* This implementation returns the underlying File's length.
*/
@Override
public long contentLength() throws IOException {
return this.file.length();
}
/**
* This implementation creates a FileSystemResource, applying the given path
* relative to the path of the underlying file of this resource descriptor.
*
* @see org.springframework.util.StringUtils#applyRelativePath(String,
* String)
*/
@Override
public StreamResource createRelative(String relativePath) {
String pathToUse = StringUtils2.applyRelativePath(this.path, relativePath);
return new FileStreamResource(pathToUse);
}
/**
* This implementation returns the name of the file.
*
* @see java.io.File#getName()
*/
@Override
public String getFilename() {
return this.file.getName();
}
/**
* This implementation returns a description that includes the absolute path
* of the file.
*
* @see java.io.File#getAbsolutePath()
*/
@Override
public String getDescription() {
return "file [" + this.file.getAbsolutePath() + "]";
}
/**
* This implementation compares the underlying File references.
*/
@Override
public boolean equals(Object obj) {
return (obj == this || (obj instanceof FileStreamResource && this.path.equals(((FileStreamResource) obj).path)));
}
/**
* This implementation returns the hash code of the underlying File
* reference.
*/
@Override
public int hashCode() {
return this.path.hashCode();
}
}