001 /* 002 * Copyright (C) 2012 eXo Platform SAS. 003 * 004 * This is free software; you can redistribute it and/or modify it 005 * under the terms of the GNU Lesser General Public License as 006 * published by the Free Software Foundation; either version 2.1 of 007 * the License, or (at your option) any later version. 008 * 009 * This software is distributed in the hope that it will be useful, 010 * but WITHOUT ANY WARRANTY; without even the implied warranty of 011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 012 * Lesser General Public License for more details. 013 * 014 * You should have received a copy of the GNU Lesser General Public 015 * License along with this software; if not, write to the Free 016 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 017 * 02110-1301 USA, or see the FSF site: http://www.fsf.org. 018 */ 019 020 package org.crsh.text; 021 022 import java.io.Closeable; 023 import java.io.IOException; 024 import java.io.Writer; 025 026 public class RenderWriter extends Writer implements Screenable { 027 028 /** . */ 029 final ScreenContext out; 030 031 /** . */ 032 private final Closeable closeable; 033 034 /** . */ 035 private boolean closed; 036 037 /** . */ 038 private boolean empty; 039 040 public RenderWriter(ScreenContext out) throws NullPointerException { 041 this(out, null); 042 } 043 044 public RenderWriter(ScreenContext out, Closeable closeable) throws NullPointerException { 045 if (out == null) { 046 throw new NullPointerException("No null appendable expected"); 047 } 048 049 // 050 this.out = out; 051 this.empty = true; 052 this.closeable = closeable; 053 } 054 055 public boolean isEmpty() { 056 return empty; 057 } 058 059 public RenderWriter append(CharSequence s) throws IOException { 060 empty &= s.length() == 0; 061 out.append(s); 062 return this; 063 } 064 065 public Screenable append(Style style) throws IOException { 066 out.append(style); 067 return this; 068 } 069 070 public Screenable cls() throws IOException { 071 out.cls(); 072 return this; 073 } 074 075 @Override 076 public void write(char[] cbuf, int off, int len) throws IOException { 077 if (closed) { 078 throw new IOException("Already closed"); 079 } 080 if (len > 0) { 081 out.append(new String(cbuf, off, len)); 082 } 083 } 084 085 @Override 086 public void flush() throws IOException { 087 if (closed) { 088 throw new IOException("Already closed"); 089 } 090 try { 091 out.flush(); 092 } 093 catch (IOException e) { 094 throw e; 095 } 096 catch (Exception e) { 097 // e.printStackTrace(); 098 // just swallow ? 099 } 100 } 101 102 @Override 103 public void close() throws IOException { 104 if (!closed) { 105 closed = true; 106 if (closeable != null) { 107 closeable.close(); 108 } 109 } 110 } 111 }