package org.lilystudio.smarty4j.statement.function;
import static org.objectweb.asm.Opcodes.*;
import java.util.Map;
import org.lilystudio.smarty4j.Analyzer;
import org.lilystudio.smarty4j.Operation;
import org.lilystudio.smarty4j.ParseException;
import org.lilystudio.smarty4j.Template;
import org.lilystudio.smarty4j.expression.check.CheckExpression;
import org.lilystudio.smarty4j.expression.check.TranslateCheck;
import org.lilystudio.smarty4j.statement.Block;
import org.lilystudio.smarty4j.statement.ILoop;
import org.lilystudio.smarty4j.statement.ParameterCharacter;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
/**
* 循环函数，完整的书写格式如下：
*
* <pre>
* {while 条件1}
* 表达式
* {/while}
* </pre>
*
* @version 1.0.0, 2010/10/01
* @author 欧阳先伟
* @since Smarty 1.0
*/
public class $while extends Block implements ILoop {
/** 循环结构块中的条件表达式 */
private CheckExpression check;
/** 循环开始标签 */
private Label startLabel = new Label();
/** 循环结束标签 */
private Label endLabel = new Label();
public Label getStartLabel() {
return startLabel;
}
public Label getEndLabel() {
return endLabel;
}
public void restore(MethodVisitor mw, Map<String, Integer> variableNames) {
}
@Override
public void syntax(Template template, Object[] words, int wordSize)
throws ParseException {
check = new TranslateCheck(Analyzer.mergeExpression(words, 3, wordSize,
Operation.FLOAT));
}
public ParameterCharacter[] getDefinitions() {
return null;
}
@Override
public void scan(Template template) {
super.scan(template);
check.scan(template);
}
@Override
public void parse(MethodVisitor mw, int local,
Map<String, Integer> variableNames) {
/* 循环语句块开始位置 */
Label block = new Label();
check.setCheckLabel(block, endLabel);
mw.visitLabel(startLabel);
check.parse(mw, local, variableNames);
mw.visitJumpInsn(IFEQ, endLabel);
mw.visitLabel(block);
super.parse(mw, local, variableNames);
mw.visitJumpInsn(GOTO, startLabel);
mw.visitLabel(endLabel);
}
}