sql 语句对应关系显示

import

java.util.HashMap;

import

java.util.Map;

import

java.util.Map.Entry;

public

class SqlStringParseDemo {

publicstaticvoid main(String[] args) {

String

sql = "Select {a.*},{b.*},{c.*} from tableA a,tableB b,tableC c";

// key: a, value: tableA a

Map<String, String>

m = new HashMap();

relevantAliasTable(

m, sql);

printAliasTable(

m);

 

}

privatestaticvoid printAliasTable(Map<String, String> m) {

for (Entry<String, String> obj : m.entrySet()) {

 

System.

out.println(obj.getKey() + " " + obj.getValue());

 

}

 

}

privatestaticvoid relevantAliasTable(Map<String, String> m, String sql) {

 

String[]

elementSelect = getElement(sql);

String[]

tableAliasFrom = getTableAlias(sql);

putElementsToMap(

m, elementSelect);

putTableAliasToMap(

m, tableAliasFrom);

 

}

privatestaticvoid putTableAliasToMap(Map<String, String> m, String[] tableAliasFrom) {

for(String obj:tableAliasFrom){

String[]

arr=obj.split(" ");

m.put("{"+arr[1]+".*" +"}",obj);

 

}

 

}

privatestaticvoid putElementsToMap(Map<String, String> m, String[] elementSelect) {

// for (String obj : elementSelect) {

//

// m.put(obj, "");

// }

//

// //System.out.println(m);

 

}

privatestatic String[] getTableAlias(String sql) {

intbeginIndexOfTableAlias = sql.indexOf("from") + "from".length() + 1;

intendIndexOfTableAlias = sql.length();

String

tableAlias = sql.substring(beginIndexOfTableAlias, endIndexOfTableAlias).trim();

 

String[]

arr = tableAlias.split(",");

 

　

　

returnarr;

}

privatestatic String[] getElement(String sql) {

intbeginIndexOfElement = "Select".length() + 1;

intendIndexOfElement = sql.indexOf("from");

String

tableAlias = sql.substring(beginIndexOfElement, endIndexOfElement).trim();

 

String[]

arr1 = tableAlias.split(",");

returnarr1;

}

 

}