File getAbsoluteFile Returns the absolute form of this abstract pathname. String getAbsolutePath Returns the absolute pathname string of this abstract pathname. File getCanonicalFile Returns the canonical form of this abstract pathname. String getCanonicalPath Returns the canonical pathname string of this abstract pathname.
String getName Returns the name of the file or directory denoted by this abstract pathname. String getParent Returns the pathname string of this abstract pathname's parent, or null if this pathname does not name a parent directory. File getParentFile Returns the abstract pathname of this abstract pathname's parent, or null if this pathname does not name a parent directory. String getPath Converts this abstract pathname into a pathname string. String [] list Returns an array of strings naming the files and directories in the directory denoted by this abstract pathname.
String [] list FilenameFilter filter Returns an array of strings naming the files and directories in the directory denoted by this abstract pathname that satisfy the specified filter. File [] listFiles Returns an array of abstract pathnames denoting the files in the directory denoted by this abstract pathname. File [] listFiles FileFilter filter Returns an array of abstract pathnames denoting the files and directories in the directory denoted by this abstract pathname that satisfy the specified filter.
File [] listFiles FilenameFilter filter Returns an array of abstract pathnames denoting the files and directories in the directory denoted by this abstract pathname that satisfy the specified filter. Path toPath Returns a java. Path object constructed from the this abstract path.
String toString Returns the pathname string of this abstract pathname. This method does not automatically escape characters that are illegal in URLs. Methods inherited from class java. Object clone , finalize , getClass , notify , notifyAll , wait , wait , wait Field Detail separatorChar public static final char separatorChar The system-dependent default name-separator character.
This field is initialized to contain the first character of the value of the system property file. See Also: System. String separator public static final String separator The system-dependent default name-separator character, represented as a string for convenience. This string contains a single character, namely separatorChar. This field is initialized to contain the first character of the value of the system property path.
This character is used to separate filenames in a sequence of files given as a path list. String pathSeparator public static final String pathSeparator The system-dependent path-separator character, represented as a string for convenience. This string contains a single character, namely pathSeparatorChar. Constructor Detail File public File String pathname Creates a new File instance by converting the given pathname string into an abstract pathname.
If the given string is the empty string, then the result is the empty abstract pathname. Parameters: pathname - A pathname string Throws: NullPointerException - If the pathname argument is null File public File String parent, String child Creates a new File instance from a parent pathname string and a child pathname string. If parent is null then the new File instance is created as if by invoking the single-argument File constructor on the given child pathname string.
Otherwise the parent pathname string is taken to denote a directory, and the child pathname string is taken to denote either a directory or a file. If the child pathname string is absolute then it is converted into a relative pathname in a system-dependent way. If parent is the empty string then the new File instance is created by converting child into an abstract pathname and resolving the result against a system-dependent default directory.
Otherwise each pathname string is converted into an abstract pathname and the child abstract pathname is resolved against the parent. Parameters: parent - The parent pathname string child - The child pathname string Throws: NullPointerException - If child is null File public File File parent, String child Creates a new File instance from a parent abstract pathname and a child pathname string.
Otherwise the parent abstract pathname is taken to denote a directory, and the child pathname string is taken to denote either a directory or a file. If parent is the empty abstract pathname then the new File instance is created by converting child into an abstract pathname and resolving the result against a system-dependent default directory. The exact form of a file: URI is system-dependent, hence the transformation performed by this constructor is also system-dependent.
For a given abstract pathname f it is guaranteed that new File f. This relationship typically does not hold, however, when a file: URI that is created in a virtual machine on one operating system is converted into an abstract pathname in a virtual machine on a different operating system. Parameters: uri - An absolute, hierarchical URI with a scheme equal to "file" , a non-empty path component, and undefined authority, query, and fragment components Throws: NullPointerException - If uri is null IllegalArgumentException - If the preconditions on the parameter do not hold Since: 1.
This is just the last name in the pathname's name sequence. If the pathname's name sequence is empty, then the empty string is returned.
Returns: The name of the file or directory denoted by this abstract pathname, or the empty string if this pathname's name sequence is empty getParent public String getParent Returns the pathname string of this abstract pathname's parent, or null if this pathname does not name a parent directory.
The parent of an abstract pathname consists of the pathname's prefix, if any, and each name in the pathname's name sequence except for the last. If the name sequence is empty then the pathname does not name a parent directory. Returns: The pathname string of the parent directory named by this abstract pathname, or null if this pathname does not name a parent getParentFile public File getParentFile Returns the abstract pathname of this abstract pathname's parent, or null if this pathname does not name a parent directory.
Returns: The abstract pathname of the parent directory named by this abstract pathname, or null if this pathname does not name a parent Since: 1. The resulting string uses the default name-separator character to separate the names in the name sequence.
Returns: The string form of this abstract pathname isAbsolute public boolean isAbsolute Tests whether this abstract pathname is absolute. The definition of absolute pathname is system dependent. Returns: true if this abstract pathname is absolute, false otherwise getAbsolutePath public String getAbsolutePath Returns the absolute pathname string of this abstract pathname.
If this abstract pathname is already absolute, then the pathname string is simply returned as if by the getPath method. If this abstract pathname is the empty abstract pathname then the pathname string of the current user directory, which is named by the system property user. Otherwise this pathname is resolved in a system-dependent way. On UNIX systems, a relative pathname is made absolute by resolving it against the current user directory. On Microsoft Windows systems, a relative pathname is made absolute by resolving it against the current directory of the drive named by the pathname, if any; if not, it is resolved against the current user directory.
Returns: The absolute pathname string denoting the same file or directory as this abstract pathname Throws: SecurityException - If a required system property value cannot be accessed. Equivalent to new File this. Returns: The absolute abstract pathname denoting the same file or directory as this abstract pathname Throws: SecurityException - If a required system property value cannot be accessed.
Since: 1. A canonical pathname is both absolute and unique. The precise definition of canonical form is system-dependent. This method first converts this pathname to absolute form if necessary, as if by invoking the getAbsolutePath method, and then maps it to its unique form in a system-dependent way. This typically involves removing redundant names such as ". Every pathname that denotes an existing file or directory has a unique canonical form.
Every pathname that denotes a nonexistent file or directory also has a unique canonical form. The canonical form of the pathname of a nonexistent file or directory may be different from the canonical form of the same pathname after the file or directory is created.
Similarly, the canonical form of the pathname of an existing file or directory may be different from the canonical form of the same pathname after the file or directory is deleted. FileDescriptor method denies read access to the file Since: 1. Converts this abstract pathname into a file: URL. The exact form of the URL is system-dependent. If it can be determined that the file denoted by this abstract pathname is a directory, then the resulting URL will end with a slash.
The exact form of the URI is system-dependent. If it can be determined that the file denoted by this abstract pathname is a directory, then the resulting URI will end with a slash. For a given abstract pathname f , it is guaranteed that new File f. Due to the system-dependent nature of abstract pathnames, however, this relationship typically does not hold when a file: URI that is created in a virtual machine on one operating system is converted into an abstract pathname in a virtual machine on a different operating system.
The authority component is undefined, meaning that it is represented as null. The Path class defines the toUri method to encode the server name in the authority component of the resulting URI. The toPath method may be used to obtain a Path representing this abstract pathname. Returns: An absolute, hierarchical URI with a scheme equal to "file" , a path representing this abstract pathname, and undefined authority, query, and fragment components Throws: SecurityException - If a required system property value cannot be accessed.
Returns: true if and only if the file specified by this abstract pathname exists and can be read by the application; false otherwise Throws: SecurityException - If a security manager exists and its SecurityManager. String method denies read access to the file canWrite public boolean canWrite Tests whether the application can modify the file denoted by this abstract pathname.
The following code sample shows how to create a zip file system and copy a file to the new zip file system. Click here to file a bug against Eclipse Web Tools Platform. Click here to file a bug against Eclipse Platform. Click here to file a bug against Maven integration for web projects. Click here to report an issue against Eclipse Wild Web Developer incubating.
Package suited for development of Eclipse itself at Eclipse. Click here to file a bug against Eclipse Git team provider. Before you can create an application to download and create datasets for you, you'll need to know the basics required for automating file downloads via Java code.
Getting the basics right will help you use them to your own specific set of needs, whether it's for a backend server application or Android app. There are multiple ways to download a file using Java code. Here are just a few ways of how you can accomplish the task:. The most easily available and a basic package available for downloading a file from internet using Java code is the Java IO package.
Here we will be using the BufferedInputStream and the URL classes to open and read a file on a given address to a file on our local system. The reason we use the BufferedInputStream class instead of the InputStream is its buffering ability that gives our code a performance boost. Before we dive deeper into the coding aspect let's take an overview of the classes and the individual functions we will be using in the process.
The java. URL class in Java is a built-in library that offers multiple methods to access and manipulate data on the internet. In this case, we will be using the openStream function of the URL class. The method signature for the openStream function is:.
The openStream function works on an object of the URL class. The URL class opens up a connection to the given URL and the openStream method returns an input stream which is used to read data from the connection.
These classes are used for reading from a file and writing to it, respectively. The contents are read as bytes and copied to a file in the local directory using the FileOutputStream. To lower the number of lines of code we can use the Files class available from Java 7. Click OK to close the environment variables panel.
A new command prompt should open in which the following command can be entered to verify the installed Java version:. Go to the Oracle Java Archive page. Only developers and Enterprise administrators should download these releases. For current Java releases, please consult the Oracle Software Download page. Java Version 7. Here is the direct link to download the jdk 1. Click Next and then Close to finish installing Java. A new command prompt should open in which the following command can be entered to verify the installed Java version: The result should be as shown below.
This concludes the setting up and configuring JDK 1.
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