Unless otherwise noted, passing a null argument to a constructor
or method in this class will cause a NullPointerException to be
thrown.
getNextEntry() method is used to read the next ZIP file entry
(Local file (LOC) header record in the ZIP format) and position the stream at
the entry's file data. The file data may read using one of the
ZipInputStream read methods such
as read or readAllBytes().
For example:
Path jar = Path.of("foo.jar"); try (InputStream is = Files.newInputStream(jar); ZipInputStream zis = new ZipInputStream(is)) { ZipEntry ze; while ((ze = zis.getNextEntry()) != null) { var bytes = zis.readAllBytes(); System.out.printf("Entry: %s, bytes read: %s%n", ze.getName(), bytes.length); } }
API Note
The LOC header contains metadata about the ZIP file entry. ZipInputStream
does not read the Central directory (CEN) header for the entry and therefore
will not have access to its metadata such as the external file attributes.
ZipFile may be used when the information stored within
the CEN header is required.
| Modifier and Type | Field and Description |
|---|---|
| private byte[] | |
| private boolean | |
| private CRC32 | |
| private static final int | |
| private ZipEntry | |
| private boolean | |
| private boolean | |
| private int | |
| private long | |
| private static final int | |
| private byte[] | |
| private ZipCoder |
| Access | Constructor and Description |
|---|---|
| public | |
| public | ZipInputStream(InputStream
the actual input stream in, Charset The charset to be
used to decode the ZIP entry name (ignored if the
language
encoding bit of the ZIP entry's general purpose bit
flag is set). charset)Creates a new ZIP input stream. |
| Modifier and Type | Method and Description |
|---|---|
| public int | Returns: 0 when end of stream is detected for the current ZIP entry orcloseEntry() has been called on the current ZIP entry, otherwise 1.Overrides java. Returns 0 when end of stream is detected for the current ZIP entry or
|
| public void | close()
Overrides java. Implements java. Closes this input stream and releases any system resources associated with the stream. |
| public void | |
| protected ZipEntry | Returns: the ZipEntry just createdthe ZIP file entry name name)Creates a new |
| private void | ensureOpen()
Hides java. Check to make sure that this stream has not been closed |
| private boolean | expect64BitDataDescriptor(byte[]
the LOC extra field to look for a Zip64 field in extra, int the value of the 'general purpose bit flag' field in the LOC flag, long the value of the 'compressed size' field in the LOC csize, long the value of the 'uncompressed size' field in the LOC size)Determine whether the |
| public ZipEntry | Returns: the next ZIP file entry, or null if there are no more entriesReads the next ZIP file entry and positions the stream at the beginning of the entry data. |
| public int | Returns: the byte read, or -1 if the end of the stream is reachedOverrides java. Reads the next byte of data from the input stream for the current ZIP entry. |
| public int | Returns: the actual number of bytes read, or -1 if the end of the entry is reachedthe buffer into which the data is read b, int the start offset in the destination array off, int bthe maximum number of bytes read len)Overrides java. Reads the requested number of bytes from the input stream into the given byte array for the current ZIP entry returning the number of inflated bytes. |
| public byte[] | readAllBytes()
Overrides java. Reads all remaining bytes from the input stream for the current ZIP entry. |
| private void | |
| private void | |
| private ZipEntry | |
| public byte[] | readNBytes(int len)
Overrides java. Reads up to a specified number of bytes from the input stream for the current ZIP entry. |
| public int | readNBytes(byte[] b, int off, int len)
Overrides java. Reads the requested number of bytes from the input stream into the given byte array for the current ZIP entry returning the number of inflated bytes. |
| public long | Returns: the actual number of bytes skippedthe number of bytes to skip n)Overrides java. Skips over and discards |
| public void | skipNBytes(long n)
Overrides java. Skips over and discards exactly |
| public long | transferTo(OutputStream out)
Overrides java. Reads all bytes from this input stream for the current ZIP entry and writes the bytes to the given output stream in the order that they are read. |
| b | back to summary |
|---|---|
| private byte[] b | |
| closed | back to summary |
|---|---|
| private boolean closed | |
| crc | back to summary |
|---|---|
| private CRC32 crc | |
| DEFLATED | back to summary |
|---|---|
| private static final int DEFLATED | |
| entry | back to summary |
|---|---|
| private ZipEntry entry | |
| entryEOF | back to summary |
|---|---|
| private boolean entryEOF | |
| expect64BitDataDescriptor | back to summary |
|---|---|
| private boolean expect64BitDataDescriptor | |
| flag | back to summary |
|---|---|
| private int flag | |
| remaining | back to summary |
|---|---|
| private long remaining | |
| STORED | back to summary |
|---|---|
| private static final int STORED | |
| tmpbuf | back to summary |
|---|---|
| private byte[] tmpbuf | |
| zc | back to summary |
|---|---|
| private ZipCoder zc | |
| ZipInputStream | back to summary |
|---|---|
| public ZipInputStream(InputStream in) Creates a new ZIP input stream. The UTF-8
| |
| ZipInputStream | back to summary |
|---|---|
| public ZipInputStream(InputStream in, Charset charset) Creates a new ZIP input stream.
| |
| available | back to summary |
|---|---|
| public int available() throws IOException Overrides java. Returns 0 when end of stream is detected for the current ZIP entry or
Programs should not count on this method to return the actual number of bytes that could be read without blocking.
| |
| close | back to summary |
|---|---|
| public void close() throws IOException Overrides java. Implements java. Closes this input stream and releases any system resources associated with the stream.
| |
| closeEntry | back to summary |
|---|---|
| public void closeEntry() throws IOException Closes the current ZIP entry and positions the stream for reading the next entry.
| |
| createZipEntry | back to summary |
|---|---|
| protected ZipEntry createZipEntry(String name) Creates a new | |
| ensureOpen | back to summary |
|---|---|
| private void ensureOpen() throws IOException Hides java. Check to make sure that this stream has not been closed | |
| expect64BitDataDescriptor | back to summary |
|---|---|
| private boolean expect64BitDataDescriptor(byte[] extra, int flag, long csize, long size) Determine whether the
| |
| getNextEntry | back to summary |
|---|---|
| public ZipEntry getNextEntry() throws IOException Reads the next ZIP file entry and positions the stream at the beginning of the entry data.
| |
| read | back to summary |
|---|---|
| public int read() throws IOException Overrides java. Reads the next byte of data from the input stream for the current ZIP entry. This method will block until enough input is available for decompression.
| |
| read | back to summary |
|---|---|
| public int read(byte[] b, int off, int len) throws IOException Overrides java. Reads the requested number of bytes from the input stream into the given
byte array for the current ZIP entry returning the number of
inflated bytes. If
If the current entry is compressed and this method returns a nonzero
integer n then
| |
| readAllBytes | back to summary |
|---|---|
| public byte[] readAllBytes() throws IOException Overrides java. Reads all remaining bytes from the input stream for the current ZIP entry. This method blocks until all remaining bytes have been read and end of stream is detected, or an exception is thrown. This method does not close the input stream. When this stream reaches end of stream, further invocations of this method will return an empty byte array. Note that this method is intended for simple cases where it is convenient to read all bytes into a byte array. It is not intended for reading input streams with large amounts of data. If an I/O error occurs reading from the input stream, then it may do so after some, but not all, bytes have been read. Consequently, the input stream may not be at end of stream and may be in an inconsistent state. It is strongly recommended that the stream be promptly closed if an I/O error occurs.
| |
| readEnd | back to summary |
|---|---|
| private void readEnd(ZipEntry e) throws IOException Reads end of deflated entry as well as EXT descriptor if present. Local headers for DEFLATED entries may optionally be followed by a data descriptor, and that data descriptor may optionally contain a leading signature (EXTSIG). From the ZIP spec http://www.pkware.com/documents/casestudies/APPNOTE.TXT """Although not originally assigned a signature, the value 0x08074b50 has commonly been adopted as a signature value for the data descriptor record. Implementers should be aware that ZIP files may be encountered with or without this signature marking data descriptors and should account for either case when reading ZIP files to ensure compatibility.""" | |
| readFully | back to summary |
|---|---|
| private void readFully(byte[] b, int off, int len) throws IOException | |
| readLOC | back to summary |
|---|---|
| private ZipEntry readLOC() throws IOException | |
| readNBytes | back to summary |
|---|---|
| public byte[] readNBytes(int len) throws IOException Overrides java. Reads up to a specified number of bytes from the input stream for the current ZIP entry. This method blocks until the requested number of bytes has been read, end of stream is detected, or an exception is thrown. This method does not close the input stream. The length of the returned array equals the number of bytes read
from the stream. If When this stream reaches end of stream, further invocations of this method will return an empty byte array. Note that this method is intended for simple cases where it is
convenient to read the specified number of bytes into a byte array. The
total amount of memory allocated by this method is proportional to the
number of bytes read from the stream which is bounded by If an I/O error occurs reading from the input stream, then it may do so after some, but not all, bytes have been read. Consequently, the input stream may not be at end of stream and may be in an inconsistent state. It is strongly recommended that the stream be promptly closed if an I/O error occurs. Implementation Note This method calls
| |
| readNBytes | back to summary |
|---|---|
| public int readNBytes(byte[] b, int off, int len) throws IOException Overrides java. Reads the requested number of bytes from the input stream into the given
byte array for the current ZIP entry returning the number of
inflated bytes.
This method blocks until In the case where end of stream is reached before If The first byte read is stored into element If an I/O error occurs reading from the input stream, then it may do
so after some, but not all, bytes of
| |
| skip | back to summary |
|---|---|
| public long skip(long n) throws IOException Overrides java. Skips over and discards
| |
| skipNBytes | back to summary |
|---|---|
| public void skipNBytes(long n) throws IOException Overrides java. Skips over and discards exactly This method blocks until the requested number of bytes has been skipped, end of file is reached, or an exception is thrown. If end of stream is reached before the stream is at the desired
position, then an If an I/O error occurs, then the input stream may be in an inconsistent state. It is strongly recommended that the stream be promptly closed if an I/O error occurs.
| |
| transferTo | back to summary |
|---|---|
| public long transferTo(OutputStream out) throws IOException Overrides java. Reads all bytes from this input stream for the current ZIP entry and writes the bytes to the given output stream in the order that they are read. On return, this input stream will be at end of stream. This method does not close either stream. This method may block indefinitely reading from the input stream, or writing to the output stream. The behavior for the case where the input and/or output stream is asynchronously closed, or the thread interrupted during the transfer, is highly input and output stream specific, and therefore not specified.
If the total number of bytes transferred is greater than Long#MAX_VALUE, then If an I/O error occurs reading from the input stream or writing to the output stream, then it may do so after some bytes have been read or written. Consequently, the input stream may not be at end of stream and one, or both, streams may be in an inconsistent state. It is strongly recommended that both streams be promptly closed if an I/O error occurs.
| |