java.util.jar: public class: JarOutputStream

java.util.jar
public class: JarOutputStream [javadoc | source]

java.lang.Object
   java.io.OutputStream
      java.io.FilterOutputStream
         java.util.zip.DeflaterOutputStream
            java.util.zip.ZipOutputStream
               java.util.jar.JarOutputStream

All Implemented Interfaces:
ZipConstants, Flushable, Closeable

The JarOutputStream class is used to write the contents of a JAR file to any output stream. It extends the class java.util.zip.ZipOutputStream with support for writing an optional Manifest entry. The Manifest can be used to specify meta-information about the JAR file and its entries.

Also see:

Manifest

java.util.zip.ZipOutputStream

author: David - Connelly

since: 1.2 -

Fields inherited from java.util.zip.ZipOutputStream:
STORED, DEFLATED

Fields inherited from java.util.zip.DeflaterOutputStream:
def, buf, usesDefaultDeflater

Fields inherited from java.io.FilterOutputStream:
out

Constructor:

Constructor:
public JarOutputStream(OutputStream out) throws IOException { super(out); } Creates a new `JarOutputStream` with no manifest. Parameters: `out` - the actual output stream Throws: `IOException` - if an I/O error has occurred exception: `IOException` - if an I/O error has occurred
public JarOutputStream(OutputStream out, Manifest man) throws IOException { super(out); if (man == null) { throw new NullPointerException("man"); } ZipEntry e = new ZipEntry(JarFile.MANIFEST_NAME); putNextEntry(e); man.write(new BufferedOutputStream(this)); closeEntry(); } Creates a new `JarOutputStream` with the specified `Manifest`. The manifest is written as the first entry to the output stream. Parameters: `out` - the actual output stream `man` - the optional `Manifest` Throws: `IOException` - if an I/O error has occurred exception: `IOException` - if an I/O error has occurred

 public JarOutputStream(OutputStream out) throws IOException {
        super(out);
}

JarOutputStream

Parameters:

out - the actual output stream

Throws:

IOException - if an I/O error has occurred

exception: IOException - if an I/O error has occurred

 public JarOutputStream(OutputStream out,
    Manifest man) throws IOException {
                                                
        super(out);
        if (man == null) {
            throw new NullPointerException("man");
        }
        ZipEntry e = new ZipEntry(JarFile.MANIFEST_NAME);
        putNextEntry(e);
        man.write(new BufferedOutputStream(this));
        closeEntry();
}

JarOutputStream

Manifest

Parameters:

out - the actual output stream

man - the optional Manifest

Throws:

IOException - if an I/O error has occurred

exception: IOException - if an I/O error has occurred

Method from java.util.jar.JarOutputStream Summary:
putNextEntry

Methods from java.util.zip.ZipOutputStream:
close, closeEntry, finish, getUTF8Length, putNextEntry, setComment, setLevel, setMethod, write

Methods from java.util.zip.DeflaterOutputStream:
close, deflate, finish, write, write

Methods from java.io.FilterOutputStream:
close, flush, write, write, write

Methods from java.io.OutputStream:
close, flush, write, write, write

Methods from java.lang.Object:
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method from java.util.jar.JarOutputStream Detail:
public void putNextEntry(ZipEntry ze) throws IOException { if (firstEntry) { // Make sure that extra field data for first JAR // entry includes JAR magic number id. byte[] edata = ze.getExtra(); if (edata == null \|\| !hasMagic(edata)) { if (edata == null) { edata = new byte[4]; } else { // Prepend magic to existing extra data byte[] tmp = new byte[edata.length + 4]; System.arraycopy(edata, 0, tmp, 4, edata.length); edata = tmp; } set16(edata, 0, JAR_MAGIC); // extra field id set16(edata, 2, 0); // extra field size ze.setExtra(edata); } firstEntry = false; } super.putNextEntry(ze); } Begins writing a new JAR file entry and positions the stream to the start of the entry data. This method will also close any previous entry. The default compression method will be used if no compression method was specified for the entry. The current time will be used if the entry has no set modification time.

Method from java.util.jar.JarOutputStream Detail:

 public  void putNextEntry(ZipEntry ze) throws IOException {
        if (firstEntry) {
            // Make sure that extra field data for first JAR
            // entry includes JAR magic number id.
            byte[] edata = ze.getExtra();
            if (edata == null || !hasMagic(edata)) {
                if (edata == null) {
                    edata = new byte[4];
                } else {
                    // Prepend magic to existing extra data
                    byte[] tmp = new byte[edata.length + 4];
                    System.arraycopy(edata, 0, tmp, 4, edata.length);
                    edata = tmp;
                }
                set16(edata, 0, JAR_MAGIC); // extra field id
                set16(edata, 2, 0);         // extra field size
                ze.setExtra(edata);
            }
            firstEntry = false;
        }
        super.putNextEntry(ze);
}

Begins writing a new JAR file entry and positions the stream to the start of the entry data. This method will also close any previous entry. The default compression method will be used if no compression method was specified for the entry. The current time will be used if the entry has no set modification time.