io.github.wycst.wast.common.expression.compile.CompilerExprEvaluator Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of wast Show documentation
Show all versions of wast Show documentation
Wast is a high-performance Java toolset library package that includes JSON, YAML, CSV, HttpClient, JDBC and EL engines
The newest version!
package io.github.wycst.wast.common.expression.compile;
import io.github.wycst.wast.common.expression.ExprEvaluator;
import io.github.wycst.wast.common.expression.ExpressionException;
/**
* @Author: wangy
* @Date: 2022/11/6 12:42
* @Description:
*/
public final class CompilerExprEvaluator extends ExprEvaluator {
/**
* 生成表达式代码
*
* @return
*/
public String code() {
StringBuilder builder = new StringBuilder();
// 如果当前为静态执行器进行解析压缩
if (isConstantExpr()) {
Object result = evaluate();
if (result instanceof String) {
String strValue = (String) result;
if (strValue.indexOf('"') > -1) {
// Simple replacement
strValue = strValue.replace("\"", "\\\"");
}
return builder.append("\"").append(strValue).append("\"").toString();
}
return String.valueOf(result);
}
int evalType = getEvalType();
boolean negate = isNegate();
boolean logicalNot = isLogicalNot();
ExprEvaluator left = getLeft();
ExprEvaluator right = getRight();
if (evalType == EVAL_TYPE_OPERATOR) {
String leftGenerateCode = left.code();
if (right == null) {
return leftGenerateCode;
}
String rightGenerateCode = right.code();
switch (operator) {
case MULTI:
// *乘法
return builder.append(leftGenerateCode).append(" * ").append(rightGenerateCode).toString();
case DIVISION:
// /除法
return builder.append(leftGenerateCode).append(" / ").append(rightGenerateCode).toString();
case MOD:
// %取余数
return builder.append(leftGenerateCode).append(" % ").append(rightGenerateCode).toString();
case EXP:
// **指数
return builder.append("Math.pow(").append(leftGenerateCode).append(", ").append(rightGenerateCode).append(")").toString();
case PLUS:
// 加法
if(right.isNegate()) {
try {
return builder.append(leftGenerateCode).append(" - ").append(right.negate(false).code()).toString();
} finally {
// reduction
right.negate(true);
}
} else if(right.isConstantExpr() && rightGenerateCode.startsWith("-")) {
return builder.append(leftGenerateCode).append(" - ").append(rightGenerateCode.substring(1)).toString();
}
return builder.append(leftGenerateCode).append(" + ").append(rightGenerateCode).toString();
case MINUS:
// -减法（理论上代码不可达） 因为'-'统一转化为了'+'(负)
return builder.append(leftGenerateCode).append(" - ").append(rightGenerateCode).toString();
case BIT_RIGHT:
// >> 位运算右移 long
return builder.append(leftGenerateCode).append(" >> ").append(rightGenerateCode).toString();
case BIT_LEFT:
// << 位运算右移 long
return builder.append(leftGenerateCode).append(" << ").append(rightGenerateCode).toString();
case AND:
// & long
return builder.append(leftGenerateCode).append(" & ").append(rightGenerateCode).toString();
case XOR:
// ^ long
return builder.append(leftGenerateCode).append(" ^ ").append(rightGenerateCode).toString();
case OR:
// | long
return builder.append(leftGenerateCode).append(" | ").append(rightGenerateCode).toString();
case GT:
// >
return builder.append(leftGenerateCode).append(" > ").append(rightGenerateCode).toString();
case LT:
// <
return builder.append(leftGenerateCode).append(" < ").append(rightGenerateCode).toString();
case EQ:
// == Object
return builder.append(leftGenerateCode).append(" == ").append(rightGenerateCode).toString();
case GE:
// >=
return builder.append(leftGenerateCode).append(" >= ").append(rightGenerateCode).toString();
case LE:
// <=
return builder.append(leftGenerateCode).append(" <= ").append(rightGenerateCode).toString();
case NE:
// != Object
return builder.append(leftGenerateCode).append(" != ").append(rightGenerateCode).toString();
case LOGICAL_AND:
// && Boolean
return builder.append(leftGenerateCode).append(" && ").append(rightGenerateCode).toString();
case LOGICAL_OR:
// || Boolean
return builder.append(leftGenerateCode).append(" || ").append(rightGenerateCode).toString();
case IN:
// in 暂时不支持
throw new ExpressionException("暂时不支持'in'符号编译");
case OUT:
// out 暂时不支持out
throw new ExpressionException("暂时不支持'out'符号编译");
case COLON:
// : 三目运算条件
return builder.append(leftGenerateCode).append(" : ").append(rightGenerateCode).toString();
case QUESTION:
// ? 三目运算结果
return builder.append(leftGenerateCode).append(" ? ").append(rightGenerateCode).toString();
}
} else if (evalType == EVAL_TYPE_BRACKET) {
if (negate) {
return builder.append("-(").append(right.code()).append(")").toString();
}
if (logicalNot) {
return builder.append("!(").append(right.code()).append(")").toString();
}
return builder.append("(").append(right.code()).append(")").toString();
} else {
// 其他统一返回left
return left.code();
}
return null;
}
}