Java中FilterInputStream和FilterOutputStream的用法詳解。本站提示廣大學習愛好者:(Java中FilterInputStream和FilterOutputStream的用法詳解)文章只能為提供參考,不一定能成為您想要的結果。以下是Java中FilterInputStream和FilterOutputStream的用法詳解正文
FilterInputStream
FilterInputStream 的感化是用來“封裝其它的輸出流,並為它們供給額定的功效”。它的經常使用的子類有BufferedInputStream和DataInputStream。
BufferedInputStream的感化就是為“輸出流供給緩沖功效,和mark()和reset()功效”。
DataInputStream 是用來裝潢其它輸出流,它“許可運用法式以與機械有關方法從底層輸出流中讀取根本 Java 數據類型”。運用法式可使用DataOutputStream(數據輸入流)寫入由DataInputStream(數據輸出流)讀取的數據。
FilterInputStream 源碼(基於jdk1.7.40):
package java.io; public class FilterInputStream extends InputStream { protected volatile InputStream in; protected FilterInputStream(InputStream in) { this.in = in; } public int read() throws IOException { return in.read(); } public int read(byte b[]) throws IOException { return read(b, 0, b.length); } public int read(byte b[], int off, int len) throws IOException { return in.read(b, off, len); } public long skip(long n) throws IOException { return in.skip(n); } public int available() throws IOException { return in.available(); } public void close() throws IOException { in.close(); } public synchronized void mark(int readlimit) { in.mark(readlimit); } public synchronized void reset() throws IOException { in.reset(); } public boolean markSupported() { return in.markSupported(); } }
FilterOutputStream
FilterOutputStream 的感化是用來“封裝其它的輸入流,並為它們供給額定的功效”。它重要包含BufferedOutputStream, DataOutputStream和PrintStream。
(01) BufferedOutputStream的感化就是為“輸入流供給緩沖功效”。
(02) DataOutputStream 是用來裝潢其它輸入流,將DataOutputStream和DataInputStream輸出流合營應用,“許可運用法式以與機械有關方法從底層輸出流中讀寫根本 Java 數據類型”。
(03) PrintStream 是用來裝潢其它輸入流。它能為其他輸入流添加了功效,使它們可以或許便利地打印各類數據值表現情勢。
FilterOutputStream 源碼(基於jdk1.7.40):
package java.io; public class FilterOutputStream extends OutputStream { protected OutputStream out; public FilterOutputStream(OutputStream out) { this.out = out; } public void write(int b) throws IOException { out.write(b); } public void write(byte b[]) throws IOException { write(b, 0, b.length); } public void write(byte b[], int off, int len) throws IOException { if ((off | len | (b.length - (len + off)) | (off + len)) < 0) throw new IndexOutOfBoundsException(); for (int i = 0 ; i < len ; i++) { write(b[off + i]); } } public void flush() throws IOException { out.flush(); } public void close() throws IOException { try { flush(); } catch (IOException ignored) { } out.close(); } }