Urlconnection pdf

A connection to the object referenced by the URL is not created. Parameters: url - the specified URL. It will first try to load the user-specific table, defined by "content. Returns: the FileNameMap Since: 1. If there is a security manager, this method first calls the security manager's checkSetFactory method to ensure the operation is allowed.

This could result in a SecurityException. Parameters: map - the FileNameMap to be set Throws: SecurityException - if a security manager exists and its checkSetFactory method doesn't allow the operation. Since: 1. If the connect method is called when the connection has already been opened indicated by the connected field having the value true , the call is ignored. URLConnection objects go through two phases: first they are created, then they are connected. After being created, and before being connected, various options can be specified e.

After connecting, it is an error to try to set them. Operations that depend on being connected, like getContentLength, will implicitly perform the connection, if necessary. See Also: connected , getConnectTimeout , setConnectTimeout int setConnectTimeout public void setConnectTimeout int timeout Sets a specified timeout value, in milliseconds, to be used when opening a communications link to the resource referenced by this URLConnection.

If the timeout expires before the connection can be established, a java. SocketTimeoutException is raised. A timeout of zero is interpreted as an infinite timeout. Some non-standard implmentation of this method may ignore the specified timeout. To see the connect timeout set, please call getConnectTimeout.

Parameters: timeout - an int that specifies the connect timeout value in milliseconds Throws: IllegalArgumentException - if the timeout parameter is negative Since: 1. Returns: an int that indicates the connect timeout value in milliseconds Since: 1. A non-zero value specifies the timeout when reading from Input stream when a connection is established to a resource.

If the timeout expires before there is data available for read, a java. Some non-standard implementation of this method ignores the specified timeout. To see the read timeout set, please call getReadTimeout. Parameters: timeout - an int that specifies the timeout value to be used in milliseconds Throws: IllegalArgumentException - if the timeout parameter is negative Since: 1.

Returns: an int that indicates the read timeout value in milliseconds Since: 1. Note : getContentLengthLong should be preferred over this method, since it returns a long instead and is therefore more portable. If called on a connection that sets the same header multiple times with possibly different values, only the last value is returned. Parameters: name - the name of a header field. Returns: the value of the named header field, or null if there is no such field in the header.

The Map keys are Strings that represent the response-header field names. Each Map value is an unmodifiable List of Strings that represents the corresponding field values. Returns: a Map of header fields Since: 1. This form of getHeaderField exists because some connection types e. Classes for that connection type can override this method and short-circuit the parsing.

Parameters: name - the name of the header field. Default - the default value. Returns: the value of the named field, parsed as an integer.

The Default value is returned if the field is missing or malformed. Returns: the value of the named field, parsed as a long. Since: 7. The result is the number of milliseconds since January 1, GMT represented by the named field. Default - a default value. Returns: the value of the field, parsed as a date. The value of the Default argument is returned if the field is missing or malformed. This method can be used in conjunction with the getHeaderFieldKey method to iterate through all the headers in the message.

This method first determines the content type of the object by calling the getContentType method. If this is the first time that the application has seen that specific content type, a content handler for that content type is created: If the application has set up a content handler factory instance using the setContentHandlerFactory method, the createContentHandler method of that instance is called with the content type as an argument; the result is a content handler for that content type.

If no content handler factory has yet been set up, or if the factory's createContentHandler method returns null , then the application loads the class named: sun. If the specified class does not exist, or is not a subclass of ContentHandler , then an UnknownServiceException is thrown. Returns: the object fetched. The instanceof operator should be used to determine the specific kind of object returned.

UnknownServiceException - if the protocol does not support the content type. See Also: ContentHandlerFactory. Parameters: classes - the Class array indicating the requested types Returns: the object fetched that is the first match of the type specified in the classes array. The actual and usual connection which is to the remote object is made with the help of connecting method usage. The remote object of it becomes available, and the header fields along with its contents of one of the remote object could be accessed.

The getInputStream method or function will help return all the data of the specific or specified URL in the particular stream, which can be used to read and display. This URL will be used to read and used to display the source code of the website or a blog; to get all the source code, one has to use Loops for multiple types of source code display. Some of the important methods are helpful in using to read or write or to get some info after the connection is established.

They are:. By default, the value of it is TRUE. At first, different types of java libraries are imported. What better library preferably in a public Maven repository and open-source can I use to do this? It seems to me that what you're asking is to determine if a file is textual or not. Given that, there is a solution here that seems right:.

And there is a big performance hit with inspecting every byte. But after some experiments, I settled on an algorithm that works for me. I examine the first line and declare the file to be binary if I encounter even one non-text byte. It seems a little slack, I know, but I seem to get away with it. EDIT 1: Expanding on this type of solution, it seems like a reasonable approach would be to ensure the file contains no non-ascii characters unless you're dealing with files that are non-English This could be done by checking if the file contents as a String does not match this:.

EDIT 2 You may want to try this as your regex, or something close to it. Though, I'll admit it could likely use some refining. Stack Overflow for Teams — Collaborate and share knowledge with a private group.

Viewed times. Improve this question. Mustansar Saeed Mustansar Saeed 2, 2 2 gold badges 18 18 silver badges 42 42 bronze badges. Add a comment. Active Oldest Votes. Improve this answer. Petesh Petesh Thanks for the help. Not necessarily, I've seen this sort of behaviour on android, and it doesn't actually mean there's no data - you should try to read so see if the data is being returned.