1 /** 2 * 3 * Copyright 2003-2004 The Apache Software Foundation 4 * 5 * Licensed under the Apache License, Version 2.0 (the "License"); 6 * you may not use this file except in compliance with the License. 7 * You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18 // 19 // This source code implements specifications defined by the Java 20 // Community Process. In order to remain compliant with the specification 21 // DO NOT add / change / or delete method signatures! 22 // 23 24 package javax.servlet.jsp.tagext; 25 26 import javax.servlet.jsp.JspException; 27 import javax.servlet.jsp.JspWriter; 28 29 /** 30 * A base class for defining tag handlers implementing BodyTag. 31 * 32 * <p> 33 * The BodyTagSupport class implements the BodyTag interface and adds 34 * additional convenience methods including getter methods for the 35 * bodyContent property and methods to get at the previous out JspWriter. 36 * 37 * <p> 38 * Many tag handlers will extend BodyTagSupport and only redefine a 39 * few methods. 40 */ 41 42 public class BodyTagSupport extends TagSupport implements BodyTag { 43 44 /** 45 * Default constructor, all subclasses are required to only define 46 * a public constructor with the same signature, and to call the 47 * superclass constructor. 48 * 49 * This constructor is called by the code generated by the JSP 50 * translator. 51 */ 52 53 public BodyTagSupport() { 54 super(); 55 } 56 57 /** 58 * Default processing of the start tag returning EVAL_BODY_BUFFERED. 59 * 60 * @return EVAL_BODY_BUFFERED 61 * @throws JspException if an error occurred while processing this tag 62 * @see BodyTag#doStartTag 63 */ 64 65 public int doStartTag() throws JspException { 66 return EVAL_BODY_BUFFERED; 67 } 68 69 70 /** 71 * Default processing of the end tag returning EVAL_PAGE. 72 * 73 * @return EVAL_PAGE 74 * @throws JspException if an error occurred while processing this tag 75 * @see Tag#doEndTag 76 */ 77 78 public int doEndTag() throws JspException { 79 return super.doEndTag(); 80 } 81 82 83 // Actions related to body evaluation 84 85 /** 86 * Prepare for evaluation of the body: stash the bodyContent away. 87 * 88 * @param b the BodyContent 89 * @see #doAfterBody 90 * @see #doInitBody() 91 * @see BodyTag#setBodyContent 92 */ 93 94 public void setBodyContent(BodyContent b) { 95 this.bodyContent = b; 96 } 97 98 99 /** 100 * Prepare for evaluation of the body just before the first body evaluation: 101 * no action. 102 * 103 * @throws JspException if an error occurred while processing this tag 104 * @see #setBodyContent 105 * @see #doAfterBody 106 * @see BodyTag#doInitBody 107 */ 108 109 public void doInitBody() throws JspException { 110 } 111 112 113 /** 114 * After the body evaluation: do not reevaluate and continue with the page. 115 * By default nothing is done with the bodyContent data (if any). 116 * 117 * @return SKIP_BODY 118 * @throws JspException if an error occurred while processing this tag 119 * @see #doInitBody 120 * @see BodyTag#doAfterBody 121 */ 122 123 public int doAfterBody() throws JspException { 124 return SKIP_BODY; 125 } 126 127 128 /** 129 * Release state. 130 * 131 * @see Tag#release 132 */ 133 134 public void release() { 135 bodyContent = null; 136 137 super.release(); 138 } 139 140 /** 141 * Get current bodyContent. 142 * 143 * @return the body _content. 144 */ 145 146 public BodyContent getBodyContent() { 147 return bodyContent; 148 } 149 150 151 /** 152 * Get surrounding out JspWriter. 153 * 154 * @return the enclosing JspWriter, from the bodyContent. 155 */ 156 157 public JspWriter getPreviousOut() { 158 return bodyContent.getEnclosingWriter(); 159 } 160 161 // protected fields 162 163 /** 164 * The current BodyContent for this BodyTag. 165 */ 166 protected BodyContent bodyContent; 167 }