com.anysoft.formula.DefaultFunctionHelper Maven / Gradle / Ivy
package com.anysoft.formula;
import java.util.Hashtable;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* 函数对象辅助器
*
*
* 函数对象辅助器维护了一个函数的映射表，并根据框架的要求生成相应函数的实例
* @author duanyy
* @version 1.6.4.21 [20151229 duanyy]
* - 根据sonar建议优化代码
*
* @version 1.6.7.9 [20170201 duanyy]
* - 采用SLF4j日志框架输出日志
*
* @version 1.6.12.4 [20171029 duanyy]
* - 增加floor,round,ceil等函数;
*
* @version 1.6.12.57 [20200103]
* - 增加t函数
*/
@SuppressWarnings("unchecked")
public class DefaultFunctionHelper implements FunctionHelper {
/**
* a logger of log4j
*/
protected static final Logger LOG = LoggerFactory.getLogger(FunctionHelper.class);
/**
* 父节点
*/
protected FunctionHelper parent = null;
/**
* 内置静态的函数映射表
*/
protected static Hashtable> static_mappings = new Hashtable>(); // NOSONAR
/**
* 内置的函数
*/
static {
try {
static_mappings.put("choice", (Class) Class
.forName("com.anysoft.formula.Function$Choice"));
static_mappings.put("nvl", (Class) Class
.forName("com.anysoft.formula.Function$Nvl"));
static_mappings.put("to_date", (Class) Class
.forName("com.anysoft.formula.Function$Char2Date"));
static_mappings.put("to_char", (Class) Class
.forName("com.anysoft.formula.Function$Date2Char"));
static_mappings.put("to_string", (Class) Class
.forName("com.anysoft.formula.Function$ToString"));
static_mappings.put("to_long", (Class) Class
.forName("com.anysoft.formula.Function$ToLong"));
static_mappings.put("to_double", (Class) Class
.forName("com.anysoft.formula.Function$ToDouble"));
static_mappings.put("to_bool", (Class) Class
.forName("com.anysoft.formula.Function$ToBoolean"));
static_mappings.put("to_boolean", (Class) Class
.forName("com.anysoft.formula.Function$ToBoolean"));
static_mappings.put("round", (Class) Class
.forName("com.anysoft.formula.Function$Round"));
static_mappings.put("ceil", (Class) Class
.forName("com.anysoft.formula.Function$Ceil"));
static_mappings.put("floor", (Class) Class
.forName("com.anysoft.formula.Function$Floor"));
static_mappings.put("substr", (Class) Class
.forName("com.anysoft.formula.Function$SubStr"));
static_mappings.put("instr", (Class) Class
.forName("com.anysoft.formula.Function$InStr"));
static_mappings.put("strlen", (Class) Class
.forName("com.anysoft.formula.Function$StrLen"));
static_mappings.put("match", (Class) Class
.forName("com.anysoft.formula.Function$Match"));
static_mappings.put("filter_tt", (Class) Class
.forName("com.anysoft.formula.filter.Timestamp"));
static_mappings.put("t",(Class)Class.forName("com.anysoft.formula.Function$AutoType"));
} catch (ClassNotFoundException e) {
LOG.error(e.getMessage());
}
}
/**
* 构造函数
* @param theParent 父节点
*/
public DefaultFunctionHelper(FunctionHelper theParent) {
parent = theParent;
}
/**
* 构造函数
*/
public DefaultFunctionHelper() {
this(null);
}
/**
* 注册函数映射
* @param funcName 函数名
* @param funClass 对应的函数实现的类名
*/
public static void addFunction(String funcName, Class funClass) {
static_mappings.put(funcName, funClass);
}
/**
* 注销函数映射
* @param funcName 函数名
*/
public static void removeFunction(String funcName) {
static_mappings.remove(funcName);
}
@Override
public Expression customize(String funcName) {
try {
Class found = static_mappings.get(funcName);
if (found != null) {
return found.newInstance();
}
if (parent != null) {
return parent.customize(funcName);
}
throw new FormulaException("Can not find function :" + funcName);
} catch (Exception ex) {
LOG.error(ex.getMessage());
throw new FormulaException("Can not create function :" + funcName);
}
}
}