System.out.write和System.out.printlnSystem.out.writ

System.out.write和System.out.printlnSystem.out.writ

System.out的类型为PrintStream；System.out.println('a'); 实际上调用是PrintStream的println(char c)方法；而println(char c)方法的源代码为：public void println(String x) {synchronized (this) { print(x); newLine();} }可见Println调用了print(char c)方法,print(char c)方法的源代码如下：public void print(char c) {write(String.valueOf(c));}可见调用的是write(String s)方法,write(String s)的代码为：private void write(String s) {try { synchronized (this) { ensureOpen(); textOut.write(s); textOut.flushBuffer(); charOut.flushBuffer(); if (autoFlush && (s.indexOf('\n') >= 0)) out.flush(); }}catch (InterruptedIOException x) { Thread.currentThread().interrupt();}catch (IOException x) { trouble = true;} }当字符串中含有'\n'时会刷新out,此处的out是OutStream对象的实例.println(String s)最后调用newLine() 方法,newLine()的代码如下:private void newLine() {try { synchronized (this) { ensureOpen(); textOut.newLine(); textOut.flushBuffer(); charOut.flushBuffer(); if (autoFlush) out.flush(); }}

我好好复习下