通过java来格式化sql语句(r4笔记第61天)

经常在抓取一些sql语句的时候，得到的sql文本有格式的问题，如果尝试得到执行计划，每次都会费一番周折。比如下面的sql语句，基本包含了常见的格式问题。第3行，第4行出现了断行，执行的时候就会报错。


select /*+ leading(s) index(s TABLE_BPM_STEP_INST_5IX) use_nl(s p
p step) */ s.ALLOW_CREATE, s.ASSIGNEE, s.ASYNC_RETURNED_PARAMS, s
.ATTACHER2STEP_INST, s.COMMITTER, s.CONTROL_COUNT, s.CURR_FAULT2F
AULT_INFO, s.DO_AVAIL_ON_RESUM, s.DO_FIN_ON_RESUM, s.HAS_DEPENDEN
TS, s.HAS_MARCH_REND, s.HAS_REND, s.INFLOW_BITS, s.ITER_COUNT, s.
NUM_OR_PREREQS, s.NUM_PENDING, s.NUM_PENDING_PREREQS, s.OBJID, s.
OUTFLOW_BITS, s.PARAMS, s.PARENT2PROC_INST, s.ROOT2PROC_INST, s.S
TART_TIME, s.STATUS, s.STATUS_CHANGE_TIME, s.STEP2STEP, s.TARGETE
D_BY_ALARMS, s.TRIGGERS_ALARMS, s.WAIT_TIME, s.WORKER FROM TABLE_
BPM_PROC_INST p, TABLE_BPM_STEP_INST s, TABLE_BPM_STEP step WHERE
 s.root2proc_inst = p.objid AND s.step2step = step.objid AND ( NO
T (step.step_type = 4)) AND p.root_status in (0, 14) AND s.commit
ter = :1 AND s.assignee in ('BpmInServer', 'BpmInServerSmThr', 'B
pmJms') AND s.status in (50, 55) AND s.curr_fault2fault_info is n
ull and ( p.EXEC_DOMAIN like :2 )

今天下定决心使用java来格式化了一把sql文本。格式化后的文本如下，得到的效果还是不错的。


select /*+ leading(s) index(s TABLE_BPM_STEP_INST_5IX) use_nl(s
pp step) */ s.ALLOW_CREATE, s.ASSIGNEE, s.ASYNC_RETURNED_PARAMS,
s.ATTACHER2STEP_INST, s.COMMITTER, s.CONTROL_COUNT,
s.CURR_FAULT2FAULT_INFO, s.DO_AVAIL_ON_RESUM, s.DO_FIN_ON_RESUM,
s.HAS_DEPENDENTS, s.HAS_MARCH_REND, s.HAS_REND, s.INFLOW_BITS, s.ITER_COUNT,
s.NUM_OR_PREREQS, s.NUM_PENDING, s.NUM_PENDING_PREREQS, s.OBJID,
s.OUTFLOW_BITS, s.PARAMS, s.PARENT2PROC_INST, s.ROOT2PROC_INST,
s.START_TIME, s.STATUS, s.STATUS_CHANGE_TIME, s.STEP2STEP,
s.TARGETED_BY_ALARMS, s.TRIGGERS_ALARMS, s.WAIT_TIME, s.WORKER FROM
TABLE_BPM_PROC_INST p, TABLE_BPM_STEP_INST s, TABLE_BPM_STEP step
WHERE s.root2proc_inst = p.objid AND s.step2step = step.objid AND (
NOT (step.step_type = 4)) AND p.root_status in (0, 14) AND
s.committer = :1 AND s.assignee in ('BpmInServer', 'BpmInServerSmThr',
'BpmJms') AND s.status in (50, 55) AND s.curr_fault2fault_info is
null and ( p.EXEC_DOMAIN like :2 )

对应的java代码结构如下，适当做了重构，可以在稍后把java代码封装一下。

public class FormatSql {
 public static void main(String[] args) throws IOException {

 ArrayList<String> strArr = readFromFile();  //从指定的文件中读取文件内容

        formatSQL(strArr);    //格式化sql文件

        OutputFormatSql(strArr);  //输出格式化后的sql语句

 }

完整的代码如下：

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;

public class FormatSql {
public static void main(String[] args) throws IOException {
ArrayList<String> strArr = readFromFile();
formatSQL(strArr);
OutputFormatSql(strArr);
}


private static void formatSQL(ArrayList<String> strArr) {
String tmpCurrLine;
String tmpNextLine;
for (int i = 0; i < strArr.size(); i++) {
tmpCurrLine = strArr.get(i);
// consider last line
if (strArr.size() == (i + 1)) {
tmpNextLine = "";
} else {
tmpNextLine = strArr.get(i + 1);
formatSqlLine(tmpCurrLine, tmpNextLine, strArr, i);
}

}
}


private static void OutputFormatSql(ArrayList<String> strArr) {
for (int i = 0; i < strArr.size(); i++) {
System.out.println(strArr.get(i));
}
}


private static void formatSqlLine(String tmpCurrLine, String tmpNextLine,
ArrayList<String> strArr, int i) {
String tmpCurrFormatLine;
String tmpCurrLeftLine;
for (int j = tmpCurrLine.length() - 1; j > 0;) {
if (tmpCurrLine.charAt(j) == ' ') {
tmpCurrFormatLine = tmpCurrLine.substring(0, j);
tmpCurrLeftLine = tmpCurrLine.substring(j + 1, tmpCurrLine
.length()); // keep last space
strArr.set(i, tmpCurrFormatLine);
strArr.set(i + 1, tmpCurrLeftLine + tmpNextLine);
tmpNextLine = tmpCurrLeftLine + tmpNextLine;
// System.out.println(tmpCurrFormatLine);
// System.out.println(tmpCurrLeftLine);
// System.out.println(tmpNextLine);
break;
} else {
j--;
}
}
}


private static ArrayList<String> readFromFile()
throws FileNotFoundException, IOException {
ArrayList<String> strArr = new ArrayList<String>();
FileReader reader = new FileReader("c://a.sql");
BufferedReader br = new BufferedReader(reader);
String str = null;
while ((str = br.readLine()) != null) {
strArr.add(str);
}
br.close();
reader.close();
return strArr;
}


}