Merge pull request #1162 from katzyn/misc

Reduce allocation of temporary strings

h2/src/main/org/h2/command/Parser.java

@@ -288,7 +288,7 @@ public class Parser {
             Command c = new CommandContainer(this, sql, p);
             if (hasMore) {
                 String remaining = originalSQL.substring(parseIndex);
-                if (remaining.trim().length() != 0) {
+                if (!StringUtils.isWhitespaceOrEmpty(remaining)) {
                     c = new CommandList(this, sql, c, remaining);
                 }
             }

h2/src/main/org/h2/command/dml/ScriptBase.java

@@ -29,6 +29,7 @@ import org.h2.store.fs.FileUtils;
 import org.h2.tools.CompressTool;
 import org.h2.util.IOUtils;
 import org.h2.util.SmallLRUCache;
+import org.h2.util.StringUtils;
 import org.h2.util.TempFileDeleter;
 import org.h2.value.CompareMode;
 
@@ -88,7 +89,7 @@ abstract class ScriptBase extends Prepared implements DataHandler {
     protected String getFileName() {
         if (fileNameExpr != null && fileName == null) {
             fileName = fileNameExpr.optimize(session).getValue(session).getString();
-            if (fileName == null || fileName.trim().length() == 0) {
+            if (fileName == null || StringUtils.isWhitespaceOrEmpty(fileName)) {
                 fileName = "script.sql";
             }
             fileName = SysProperties.getScriptDirectory() + fileName;

h2/src/main/org/h2/fulltext/FullText.java

@@ -596,7 +596,7 @@ public class FullText {
             // this is just to query the result set columns
             return result;
         }
-        if (text == null || text.trim().length() == 0) {
+        if (text == null || StringUtils.isWhitespaceOrEmpty(text)) {
             return result;
         }
         FullTextSettings setting = FullTextSettings.getInstance(conn);

h2/src/main/org/h2/fulltext/FullTextLucene.java

@@ -405,7 +405,7 @@ public class FullTextLucene extends FullText {
             // this is just to query the result set columns
             return result;
         }
-        if (text == null || text.trim().length() == 0) {
+        if (text == null || StringUtils.isWhitespaceOrEmpty(text)) {
             return result;
         }
         try {

h2/src/main/org/h2/index/PageDataIndex.java

@@ -9,7 +9,6 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Iterator;
-import java.util.List;
 import org.h2.api.ErrorCode;
 import org.h2.command.dml.AllColumnsForPlan;
 import org.h2.engine.Constants;

h2/src/main/org/h2/index/ScanIndex.java

@@ -10,7 +10,6 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Iterator;
-import java.util.List;
 
 import org.h2.api.ErrorCode;
 import org.h2.command.dml.AllColumnsForPlan;

h2/src/main/org/h2/server/TcpServer.java

@@ -16,9 +16,7 @@ import java.sql.SQLException;
 import java.sql.Statement;
 import java.util.ArrayList;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.HashSet;
-import java.util.Map;
 import java.util.Properties;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;

h2/src/main/org/h2/server/web/WebApp.java

@@ -250,8 +250,8 @@ public class WebApp {
     private String autoCompleteList() {
         String query = (String) attributes.get("query");
         boolean lowercase = false;
-        if (query.trim().length() > 0 &&
-                Character.isLowerCase(query.trim().charAt(0))) {
+        String tQuery = query.trim();
+        if (!tQuery.isEmpty() && Character.isLowerCase(tQuery.charAt(0))) {
             lowercase = true;
         }
         try {
@@ -281,7 +281,8 @@ public class WebApp {
                 while (sql.length() > 0 && sql.charAt(0) <= ' ') {
                     sql = sql.substring(1);
                 }
-                if (sql.trim().length() > 0 && Character.isLowerCase(sql.trim().charAt(0))) {
+                String tSql = sql.trim();
+                if (!tSql.isEmpty() && Character.isLowerCase(tSql.charAt(0))) {
                     lowercase = true;
                 }
                 Bnf bnf = session.getBnf();
@@ -320,7 +321,7 @@ public class WebApp {
                     list.add(type + "#" + key + "#" + value);
                 }
                 Collections.sort(list);
-                if (query.endsWith("\n") || query.trim().endsWith(";")) {
+                if (query.endsWith("\n") || tQuery.endsWith(";")) {
                     list.add(0, "1#(Newline)#\n");
                 }
                 StatementBuilder buff = new StatementBuilder();
@@ -1302,41 +1303,40 @@ public class WebApp {
                 return buff.toString();
             } else if (isBuiltIn(sql, "@edit")) {
                 edit = true;
-                sql = sql.substring("@edit".length()).trim();
+                sql = StringUtils.trimSubstring(sql, "@edit".length());
                 session.put("resultSetSQL", sql);
             }
             if (isBuiltIn(sql, "@list")) {
                 list = true;
-                sql = sql.substring("@list".length()).trim();
+                sql = StringUtils.trimSubstring(sql, "@list".length());
             }
             if (isBuiltIn(sql, "@meta")) {
                 metadata = true;
-                sql = sql.substring("@meta".length()).trim();
+                sql = StringUtils.trimSubstring(sql, "@meta".length());
             }
             if (isBuiltIn(sql, "@generated")) {
                 generatedKeys = Statement.RETURN_GENERATED_KEYS;
-                sql = sql.substring("@generated".length()).trim();
+                sql = StringUtils.trimSubstring(sql, "@generated".length());
             } else if (isBuiltIn(sql, "@history")) {
                 buff.append(getCommandHistoryString());
                 return buff.toString();
             } else if (isBuiltIn(sql, "@loop")) {
-                sql = sql.substring("@loop".length()).trim();
+                sql = StringUtils.trimSubstring(sql, "@loop".length());
                 int idx = sql.indexOf(' ');
                 int count = Integer.decode(sql.substring(0, idx));
-                sql = sql.substring(idx).trim();
+                sql = StringUtils.trimSubstring(sql, idx);
                 return executeLoop(conn, count, sql);
             } else if (isBuiltIn(sql, "@maxrows")) {
-                int maxrows = (int) Double.parseDouble(
-                        sql.substring("@maxrows".length()).trim());
+                int maxrows = (int) Double.parseDouble(StringUtils.trimSubstring(sql, "@maxrows".length()));
                 session.put("maxrows", Integer.toString(maxrows));
                 return "${text.result.maxrowsSet}";
             } else if (isBuiltIn(sql, "@parameter_meta")) {
-                sql = sql.substring("@parameter_meta".length()).trim();
+                sql = StringUtils.trimSubstring(sql, "@parameter_meta".length());
                 PreparedStatement prep = conn.prepareStatement(sql);
                 buff.append(getParameterResultSet(prep.getParameterMetaData()));
                 return buff.toString();
             } else if (isBuiltIn(sql, "@password_hash")) {
-                sql = sql.substring("@password_hash".length()).trim();
+                sql = StringUtils.trimSubstring(sql, "@password_hash".length());
                 String[] p = split(sql);
                 return StringUtils.convertBytesToHex(
                         SHA256.getKeyPasswordHash(p[0], p[1].toCharArray()));
@@ -1348,7 +1348,7 @@ public class WebApp {
                 profiler.startCollecting();
                 return "Ok";
             } else if (isBuiltIn(sql, "@sleep")) {
-                String s = sql.substring("@sleep".length()).trim();
+                String s = StringUtils.trimSubstring(sql, "@sleep".length());
                 int sleep = 1;
                 if (s.length() > 0) {
                     sleep = Integer.parseInt(s);
@@ -1356,7 +1356,7 @@ public class WebApp {
                 Thread.sleep(sleep * 1000);
                 return "Ok";
             } else if (isBuiltIn(sql, "@transaction_isolation")) {
-                String s = sql.substring("@transaction_isolation".length()).trim();
+                String s = StringUtils.trimSubstring(sql, "@transaction_isolation".length());
                 if (s.length() > 0) {
                     int level = Integer.parseInt(s);
                     conn.setTransactionIsolation(level);
@@ -1445,7 +1445,7 @@ public class WebApp {
         Random random = new Random(1);
         long time = System.currentTimeMillis();
         if (isBuiltIn(sql, "@statement")) {
-            sql = sql.substring("@statement".length()).trim();
+            sql = StringUtils.trimSubstring(sql, "@statement".length());
             prepared = false;
             Statement stat = conn.createStatement();
             for (int i = 0; !stop && i < count; i++) {

h2/src/main/org/h2/server/web/WebThread.java

@@ -310,7 +310,7 @@ class WebThread extends WebApp implements Runnable {
                         }
                     }
                 }
-            } else if (line.trim().length() == 0) {
+            } else if (StringUtils.isWhitespaceOrEmpty(line)) {
                 break;
             }
         }
@@ -328,7 +328,7 @@ class WebThread extends WebApp implements Runnable {
     }
 
     private static String getHeaderLineValue(String line) {
-        return line.substring(line.indexOf(':') + 1).trim();
+        return StringUtils.trimSubstring(line, line.indexOf(':') + 1);
     }
 
     @Override

h2/src/main/org/h2/store/Data.java

@@ -20,7 +20,6 @@ import java.sql.Timestamp;
 import java.util.Arrays;
 import org.h2.api.ErrorCode;
 import org.h2.engine.Constants;
-import org.h2.engine.SysProperties;
 import org.h2.message.DbException;
 import org.h2.tools.SimpleResultSet;
 import org.h2.util.Bits;

h2/src/main/org/h2/store/LobStorageBackend.java

@@ -17,7 +17,6 @@ import java.util.Arrays;
 import java.util.HashMap;
 import org.h2.api.ErrorCode;
 import org.h2.engine.Database;
-import org.h2.engine.SysProperties;
 import org.h2.jdbc.JdbcConnection;
 import org.h2.message.DbException;
 import org.h2.tools.CompressTool;

h2/src/main/org/h2/tools/RunScript.java

@@ -166,7 +166,7 @@ public class RunScript extends Tool {
             if (sql == null) {
                 break;
             }
-            if (sql.trim().length() == 0) {
+            if (StringUtils.isWhitespaceOrEmpty(sql)) {
                 continue;
             }
             boolean resultSet = stat.execute(sql);
@@ -210,8 +210,7 @@ public class RunScript extends Tool {
             }
             if (trim.startsWith("@") && StringUtils.toUpperEnglish(trim).
                     startsWith("@INCLUDE")) {
-                sql = trim;
-                sql = sql.substring("@INCLUDE".length()).trim();
+                sql = StringUtils.trimSubstring(sql, "@INCLUDE".length());
                 if (!FileUtils.isAbsolute(sql)) {
                     sql = path + SysProperties.FILE_SEPARATOR + sql;
                 }

h2/src/main/org/h2/tools/Shell.java

@@ -248,7 +248,7 @@ public class Shell extends Tool implements Runnable {
                         println("No history");
                     }
                 } else if (lower.startsWith("autocommit")) {
-                    lower = lower.substring("autocommit".length()).trim();
+                    lower = StringUtils.trimSubstring(lower, "autocommit".length());
                     if ("true".equals(lower)) {
                         conn.setAutoCommit(true);
                     } else if ("false".equals(lower)) {
@@ -258,7 +258,7 @@ public class Shell extends Tool implements Runnable {
                     }
                     println("Autocommit is now " + conn.getAutoCommit());
                 } else if (lower.startsWith("maxwidth")) {
-                    lower = lower.substring("maxwidth".length()).trim();
+                    lower = StringUtils.trimSubstring(lower, "maxwidth".length());
                     try {
                         maxColumnSize = Integer.parseInt(lower);
                     } catch (NumberFormatException e) {
@@ -445,7 +445,7 @@ public class Shell extends Tool implements Runnable {
     }
 
     private void execute(String sql) {
-        if (sql.trim().length() == 0) {
+        if (StringUtils.isWhitespaceOrEmpty(sql)) {
             return;
         }
         long time = System.nanoTime();

h2/src/main/org/h2/util/Profiler.java

@@ -249,7 +249,7 @@ public class Profiler implements Runnable {
                 if (!line.startsWith("at ")) {
                     break;
                 }
-                line = line.substring(3).trim();
+                line = StringUtils.trimSubstring(line, 3);
                 stack.add(line);
             }
             if (!stack.isEmpty()) {

h2/src/main/org/h2/util/StringUtils.java

@@ -848,7 +848,20 @@ public class StringUtils {
     }
 
     /**
-     * Trim a character from a substring. Equivalence of {@code substring(begin, end).trim()}.
+     * Trim a character from a substring. Equivalent of
+     * {@code substring(beginIndex).trim()}.
+     *
+     * @param s the string
+     * @param beginIndex start index of substring (inclusive)
+     * @return trimmed substring
+     */
+    public static String trimSubstring(String s, int beginIndex) {
+        return trimSubstring(s, beginIndex, s.length());
+    }
+
+    /**
+     * Trim a character from a substring. Equivalent of
+     * {@code substring(beginIndex, endIndex).trim()}.
      *
      * @param s the string
      * @param beginIndex start index of substring (inclusive)
@@ -969,11 +982,28 @@ public class StringUtils {
      * @return true if it is
      */
     public static boolean isNumber(String s) {
-        if (s.length() == 0) {
+        int l = s.length();
+        if (l == 0) {
             return false;
         }
-        for (char c : s.toCharArray()) {
-            if (!Character.isDigit(c)) {
+        for (int i = 0; i < l; i++) {
+            if (!Character.isDigit(s.charAt(i))) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    /**
+     * Check if the specified string is empty or contains only whitespace.
+     *
+     * @param s
+     *            the string
+     * @return whether the specified string is empty or contains only whitespace
+     */
+    public static boolean isWhitespaceOrEmpty(String s) {
+        for (int i = 0, l = s.length(); i < l; i++) {
+            if (s.charAt(i) > ' ') {
                 return false;
             }
         }